Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.
The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.
A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
The genetic constitution of individuals with respect to one member of a pair of allelic genes, or sets of genes that are closely linked and tend to be inherited together such as those of the MAJOR HISTOCOMPATIBILITY COMPLEX.
Genotypic differences observed among individuals in a population.
An individual having different alleles at one or more loci regarding a specific character.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
An individual in which both alleles at a given locus are identical.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Any method used for determining the location of and relative distances between genes on a chromosome.
Nonrandom association of linked genes. This is the tendency of the alleles of two separate but already linked loci to be found together more frequently than would be expected by chance alone.
A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).
A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.
Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.
A subtype of HLA-DRB beta chains that includes over one hundred allele variants. The HLA-DRB1 subtype is associated with several of the HLA-DR SEROLOGICAL SUBTYPES.
Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.
Variation occurring within a species in the presence or length of DNA fragment generated by a specific endonuclease at a specific site in the genome. Such variations are generated by mutations that create or abolish recognition sites for these enzymes or change the length of the fragment.
Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.
The discipline studying genetic composition of populations and effects of factors such as GENETIC SELECTION, population size, MUTATION, migration, and GENETIC DRIFT on the frequencies of various GENOTYPES and PHENOTYPES using a variety of GENETIC TECHNIQUES.
A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.
The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.
The analysis of a sequence such as a region of a chromosome, a haplotype, a gene, or an allele for its involvement in controlling the phenotype of a specific trait, metabolic pathway, or disease.
Individuals whose ancestral origins are in the southeastern and eastern areas of the Asian continent.
The parts of a transcript of a split GENE remaining after the INTRONS are removed. They are spliced together to become a MESSENGER RNA or other functional RNA.
Biochemical identification of mutational changes in a nucleotide sequence.
Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.
A group of the D-related HLA antigens found to differ from the DR antigens in genetic locus and therefore inheritance. These antigens are polymorphic glycoproteins comprising alpha and beta chains and are found on lymphoid and other cells, often associated with certain diseases.
A subclass of HLA-D antigens that consist of alpha and beta chains. The inheritance of HLA-DR antigens differs from that of the HLA-DQ ANTIGENS and HLA-DP ANTIGENS.
Genes whose loss of function or gain of function MUTATION leads to the death of the carrier prior to maturity. They may be essential genes (GENES, ESSENTIAL) required for viability, or genes which cause a block of function of an essential gene at a time when the essential gene function is required for viability.
Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.
Specific regions that are mapped within a GENOME. Genetic loci are usually identified with a shorthand notation that indicates the chromosome number and the position of a specific band along the P or Q arm of the chromosome where they are found. For example the locus 6p21 is found within band 21 of the P-arm of CHROMOSOME 6. Many well known genetic loci are also known by common names that are associated with a genetic function or HEREDITARY DISEASE.
Genes that influence the PHENOTYPE both in the homozygous and the heterozygous state.
Individuals whose ancestral origins are in the continent of Europe.
Class I human histocompatibility (HLA) surface antigens encoded by more than 30 detectable alleles on locus B of the HLA complex, the most polymorphic of all the HLA specificities. Several of these antigens (e.g., HLA-B27, -B7, -B8) are strongly associated with predisposition to rheumatoid and other autoimmune disorders. Like other class I HLA determinants, they are involved in the cellular immune reactivity of cytolytic T lymphocytes.
Genes that influence the PHENOTYPE only in the homozygous state.
A major and the second most common isoform of apolipoprotein E. In humans, Apo E4 differs from APOLIPOPROTEIN E3 at only one residue 112 (cysteine is replaced by arginine), and exhibits a lower resistance to denaturation and greater propensity to form folded intermediates. Apo E4 is a risk factor for ALZHEIMER DISEASE and CARDIOVASCULAR DISEASES.
Mutation process that restores the wild-type PHENOTYPE in an organism possessing a mutationally altered GENOTYPE. The second "suppressor" mutation may be on a different gene, on the same gene but located at a distance from the site of the primary mutation, or in extrachromosomal genes (EXTRACHROMOSOMAL INHERITANCE).
A mutation caused by the substitution of one nucleotide for another. This results in the DNA molecule having a change in a single base pair.
A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).
Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.
Tandem arrays of moderately repetitive, short (10-60 bases) DNA sequences which are found dispersed throughout the GENOME, at the ends of chromosomes (TELOMERES), and clustered near telomeres. Their degree of repetition is two to several hundred at each locus. Loci number in the thousands but each locus shows a distinctive repeat unit.
A test used to determine whether or not complementation (compensation in the form of dominance) will occur in a cell with a given mutant phenotype when another mutant genome, encoding the same mutant phenotype, is introduced into that cell.
Identification of genetic carriers for a given trait.
A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.
A mutation in which a codon is mutated to one directing the incorporation of a different amino acid. This substitution may result in an inactive or unstable product. (From A Dictionary of Genetics, King & Stansfield, 5th ed)
DNA sequences which are recognized (directly or indirectly) and bound by a DNA-dependent RNA polymerase during the initiation of transcription. Highly conserved sequences within the promoter include the Pribnow box in bacteria and the TATA BOX in eukaryotes.
An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.
Genetic loci associated with a QUANTITATIVE TRAIT.
An analysis comparing the allele frequencies of all available (or a whole GENOME representative set of) polymorphic markers in unrelated patients with a specific symptom or disease condition, and those of healthy controls to identify markers associated with a specific disease or condition.
Transmembrane proteins that form the alpha subunits of the HLA-DQ antigens.
Sequences of DNA in the genes that are located between the EXONS. They are transcribed along with the exons but are removed from the primary gene transcript by RNA SPLICING to leave mature RNA. Some introns code for separate genes.
The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.
The functional hereditary units of PLANTS.
A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.
A form of gene interaction whereby the expression of one gene interferes with or masks the expression of a different gene or genes. Genes whose expression interferes with or masks the effects of other genes are said to be epistatic to the effected genes. Genes whose expression is affected (blocked or masked) are hypostatic to the interfering genes.
A species of fruit fly much used in genetics because of the large size of its chromosomes.
Detection of a MUTATION; GENOTYPE; KARYOTYPE; or specific ALLELES associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing.
Antigens determined by leukocyte loci found on chromosome 6, the major histocompatibility loci in humans. They are polypeptides or glycoproteins found on most nucleated cells and platelets, determine tissue types for transplantation, and are associated with certain diseases.
A class of protein components which can be found in several lipoproteins including HIGH-DENSITY LIPOPROTEINS; VERY-LOW-DENSITY LIPOPROTEINS; and CHYLOMICRONS. Synthesized in most organs, Apo E is important in the global transport of lipids and cholesterol throughout the body. Apo E is also a ligand for LDL receptors (RECEPTORS, LDL) that mediates the binding, internalization, and catabolism of lipoprotein particles in cells. There are several allelic isoforms (such as E2, E3, and E4). Deficiency or defects in Apo E are causes of HYPERLIPOPROTEINEMIA TYPE III.
The functional hereditary units of FUNGI.
The relationships of groups of organisms as reflected by their genetic makeup.
Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.
A country spanning from central Asia to the Pacific Ocean.
The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.
Polymorphic class I human histocompatibility (HLA) surface antigens present on almost all nucleated cells. At least 20 antigens have been identified which are encoded by the A locus of multiple alleles on chromosome 6. They serve as targets for T-cell cytolytic responses and are involved with acceptance or rejection of tissue/organ grafts.
Individuals whose ancestral origins are in the continent of Africa.
A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.
Deletion of sequences of nucleic acids from the genetic material of an individual.
Variation in a population's DNA sequence that is detected by determining alterations in the conformation of denatured DNA fragments. Denatured DNA fragments are allowed to renature under conditions that prevent the formation of double-stranded DNA and allow secondary structure to form in single stranded fragments. These fragments are then run through polyacrylamide gels to detect variations in the secondary structure that is manifested as an alteration in migration through the gels.
Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.
Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.
The most common of the microsatellite tandem repeats (MICROSATELLITE REPEATS) dispersed in the euchromatic arms of chromosomes. They consist of two nucleotides repeated in tandem; guanine and thymine, (GT)n, is the most frequently seen.
Class I human histocompatibility (HLA) antigens encoded by a small cluster of structural genes at the C locus on chromosome 6. They have significantly lower immunogenicity than the HLA-A and -B determinants and are therefore of minor importance in donor/recipient crossmatching. Their primary role is their high-risk association with certain disease manifestations (e.g., spondylarthritis, psoriasis, multiple myeloma).
Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.
Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.
A method (first developed by E.M. Southern) for detection of DNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.
The number of copies of a given gene present in the cell of an organism. An increase in gene dosage (by GENE DUPLICATION for example) can result in higher levels of gene product formation. GENE DOSAGE COMPENSATION mechanisms result in adjustments to the level GENE EXPRESSION when there are changes or differences in gene dosage.
The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
Methods used to determine individuals' specific ALLELES or SNPS (single nucleotide polymorphisms).
A plant species of the family POACEAE. It is a tall grass grown for its EDIBLE GRAIN, corn, used as food and animal FODDER.
The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.
Proteins found in any species of fungus.
Genetic loci in the vertebrate major histocompatibility complex that encode polymorphic products which control the immune response to specific antigens. The genes are found in the HLA-D region in humans and in the I region in mice.
Microsatellite repeats consisting of three nucleotides dispersed in the euchromatic arms of chromosomes.
Genes that have a suppressor allele or suppressor mutation (SUPPRESSION, GENETIC) which cancels the effect of a previous mutation, enabling the wild-type phenotype to be maintained or partially restored. For example, amber suppressors cancel the effect of an AMBER NONSENSE MUTATION.
Proteins that originate from insect species belonging to the genus DROSOPHILA. The proteins from the most intensely studied species of Drosophila, DROSOPHILA MELANOGASTER, are the subject of much interest in the area of MORPHOGENESIS and development.
A type of mutation in which a number of NUCLEOTIDES deleted from or inserted into a protein coding sequence is not divisible by three, thereby causing an alteration in the READING FRAMES of the entire coding sequence downstream of the mutation. These mutations may be induced by certain types of MUTAGENS or may occur spontaneously.
Proteins obtained from the species SACCHAROMYCES CEREVISIAE. The function of specific proteins from this organism are the subject of intense scientific interest and have been used to derive basic understanding of the functioning similar proteins in higher eukaryotes.
Deoxyribonucleic acid that makes up the genetic material of plants.
The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.
The different ways GENES and their ALLELES interact during the transmission of genetic traits that effect the outcome of GENE EXPRESSION.

Standardized nomenclature for inbred strains of mice: sixth listing. (1/28798)

Rules for designating inbred strains of mice are presented, along with a list of strains with their origins and characteristics, a table of biochemical polymorphisms, and standard subline designations.  (+info)

Lack of genic similarity between two sibling species of drosophila as revealed by varied techniques. (2/28798)

Acrylamide gel electrophoresis was performed on the enzyme xanthine dehydrogenase in sixty isochromosomal lines of Drosophila persimilis from three geographic populations. Sequential electrophoretic analysis using varied gel concentrations and buffers revealed twenty-three alleles in this species where only five had been described previously. These new electrophoretic techniques also detected a profound increase in divergence of gene frequencies at this locus between D. persimilis and its sibling species D. pseudoobscura. The implications of these results for questions of speciation and the maintenance of genetic variability are discussed.  (+info)

Genetic heterogeneity within electrophoretic "alleles" of xanthine dehydrogenase in Drosophila pseudoobscura. (3/28798)

An experimental plan for an exhaustive determination of genic variation at structural gene loci is presented. In the initial steps of this program, 146 isochromosomal lines from 12 geographic populations of D. pseudoobscura were examined for allelic variation of xanthine dehydrogenase by the serial use of 4 different electrophoretic conditions and a head stability test. The 5 criteria revealed a total of 37 allelic classes out of the 146 genomes examined where only 6 had been previously revealed by the usual method of gel electrophoresis. This immense increase in genic variation also showed previously unsuspected population differences between the main part of the species distribution and the isolated population of Bogota population. The average heterozygosity at the Xdh locus is at least 72% in natural populations. This result, together with the very large number of alleles segregating and the pattern of allelic frequencies, has implications for theories of genetic polymorphism which are discussed.  (+info)

An overview of the evolution of overproduced esterases in the mosquito Culex pipiens. (4/28798)

Insecticide resistance genes have developed in a wide variety of insects in response to heavy chemical application. Few of these examples of adaptation in response to rapid environmental change have been studied both at the population level and at the gene level. One of these is the evolution of the overproduced esterases that are involved in resistance to organophosphate insecticides in the mosquito Culex pipiens. At the gene level, two genetic mechanisms are involved in esterase overproduction, namely gene amplification and gene regulation. At the population level, the co-occurrence of the same amplified allele in distinct geographic areas is best explained by the importance of passive transportation at the worldwide scale. The long-term monitoring of a population of mosquitoes in southern France has enabled a detailed study to be made of the evolution of resistance genes on a local scale, and has shown that a resistance gene with a lower cost has replaced a former resistance allele with a higher cost.  (+info)

Detailed methylation analysis of the glutathione S-transferase pi (GSTP1) gene in prostate cancer. (5/28798)

Glutathione-S-Transferases (GSTs) comprise a family of isoenzymes that provide protection to mammalian cells against electrophilic metabolites of carcinogens and reactive oxygen species. Previous studies have shown that the CpG-rich promoter region of the pi-class gene GSTP1 is methylated at single restriction sites in the majority of prostate cancers. In order to understand the nature of abnormal methylation of the GSTP1 gene in prostate cancer we undertook a detailed analysis of methylation at 131 CpG sites spanning the promoter and body of the gene. Our results show that DNA methylation is not confined to specific CpG sites in the promoter region of the GSTP1 gene but is extensive throughout the CpG island in prostate cancer cells. Furthermore we found that both alleles are abnormally methylated in this region. In normal prostate tissue, the entire CpG island was unmethylated, but extensive methylation was found outside the island in the body of the gene. Loss of GSTP1 expression correlated with DNA methylation of the CpG island in both prostate cancer cell lines and cancer tissues whereas methylation outside the CpG island in normal prostate tissue appeared to have no effect on gene expression.  (+info)

Identification of DNA polymorphisms associated with the V type alpha1-antitrypsin gene. (6/28798)

alpha1-Antitrypsin (alpha1-AT) is a highly polymorphic protein. The V allele of alpha1-AT has been shown to be associated with focal glomerulosclerosis (FGS) in Negroid and mixed race South African patients. To identify mutations and polymorphisms in the gene for the V allele of alpha1-AT in five South African patients with FGS nephrotic syndrome DNA sequence analysis and restriction fragment length polymorphisms of the coding exons were carried out. Four of the patients were heterozygous for the BstEII RFLP in exon III [M1(Val213)(Ala213)] and one patient was a M1(Ala213) homozygote. The mutation for the V allele was identified in exon II as Gly-148 (GGG)-->Arg (AGG) and in all patients was associated with a silent mutation at position 158 (AAC-->AAT). The patient who was homozygous for (Ala213) also had a silent mutation at position 256 in exon III (GAT-->GAC) which was not present in any of the other four patients. Although the V allele of alpha1-AT is not associated with severe plasma deficiency, it may be in linkage disequilibrium with other genes on chromosome 14 that predispose to FGS. Furthermore, the associated silent mutation at position 158 and the Ala213 polymorphism are of interest, as these could represent an evolutionary intermediate between the M1(Ala213) and M1(Val213) subtypes.  (+info)

The alphaE-catenin gene (CTNNA1) acts as an invasion-suppressor gene in human colon cancer cells. (7/28798)

The acquisition of invasiveness is a crucial step in the malignant progression of cancer. In cancers of the colon and of other organs the E-cadherin/catenin complex, which is implicated in homotypic cell-cell adhesion as well as in signal transduction, serves as a powerful inhibitor of invasion. We show here that one allele of the alphaE-catenin (CTNNA1) gene is mutated in the human colon cancer cell family HCT-8, which is identical to HCT-15, DLD-1 and HRT-18. Genetic instability, due to mutations in the HMSH6 (also called GTBP) mismatch repair gene, results in the spontaneous occurrence of invasive variants, all carrying either a mutation or exon skipping in the second alphaE-catenin allele. The alphaE-catenin gene is therefore, an invasion-suppressor gene in accordance with the two-hit model of Knudsen for tumour-suppressor genes.  (+info)

Correlation between the status of the p53 gene and survival in patients with stage I non-small cell lung carcinoma. (8/28798)

The association of p53 abnormalities with the prognosis of patients with non-small cell lung carcinoma (NSCLC) has been extensively investigated to date, however, this association is still controversial. Therefore, we investigated the prognostic significance of p53 mutations through exons 2 to 11 and p53 protein expression in 103 cases of stage I NSCLC. p53 mutations were detected in 49 of 103 (48%) tumors. Two separate mutations were detected in four tumors giving a total of 53 unique mutations in 49 tumors. Ten (19%) of mutations occurred outside exons 5-8. Positive immunohistochemical staining of p53 protein was detected in 41 of 103 (40%) tumors. The concordance rate between mutations and protein overexpression was only 69%. p53 mutations, but not expression, were significantly associated with a shortened survival of patients (P<0.001). Furthermore, we investigated the correlation between the types of p53 mutations and prognosis. p53 missense mutations rather than null mutations were associated with poor prognosis (P < 0.001 in missense mutations and P=0.243 in null mutations). These results indicated that p53 mutations, in particular missense mutations, rather than p53 expression could be a useful molecular marker for the prognosis of patients with surgically resected stage I NSCLC.  (+info)

An allele is a variant form of a gene that is located at a specific position on a specific chromosome. Alleles are alternative forms of the same gene that arise by mutation and are found at the same locus or position on homologous chromosomes.

Each person typically inherits two copies of each gene, one from each parent. If the two alleles are identical, a person is said to be homozygous for that trait. If the alleles are different, the person is heterozygous.

For example, the ABO blood group system has three alleles, A, B, and O, which determine a person's blood type. If a person inherits two A alleles, they will have type A blood; if they inherit one A and one B allele, they will have type AB blood; if they inherit two B alleles, they will have type B blood; and if they inherit two O alleles, they will have type O blood.

Alleles can also influence traits such as eye color, hair color, height, and other physical characteristics. Some alleles are dominant, meaning that only one copy of the allele is needed to express the trait, while others are recessive, meaning that two copies of the allele are needed to express the trait.

Genotype, in genetics, refers to the complete heritable genetic makeup of an individual organism, including all of its genes. It is the set of instructions contained in an organism's DNA for the development and function of that organism. The genotype is the basis for an individual's inherited traits, and it can be contrasted with an individual's phenotype, which refers to the observable physical or biochemical characteristics of an organism that result from the expression of its genes in combination with environmental influences.

It is important to note that an individual's genotype is not necessarily identical to their genetic sequence. Some genes have multiple forms called alleles, and an individual may inherit different alleles for a given gene from each parent. The combination of alleles that an individual inherits for a particular gene is known as their genotype for that gene.

Understanding an individual's genotype can provide important information about their susceptibility to certain diseases, their response to drugs and other treatments, and their risk of passing on inherited genetic disorders to their offspring.

Gene frequency, also known as allele frequency, is a measure in population genetics that reflects the proportion of a particular gene or allele (variant of a gene) in a given population. It is calculated as the number of copies of a specific allele divided by the total number of all alleles at that genetic locus in the population.

For example, if we consider a gene with two possible alleles, A and a, the gene frequency of allele A (denoted as p) can be calculated as follows:

p = (number of copies of allele A) / (total number of all alleles at that locus)

Similarly, the gene frequency of allele a (denoted as q) would be:

q = (number of copies of allele a) / (total number of all alleles at that locus)

Since there are only two possible alleles for this gene in this example, p + q = 1. These frequencies can help researchers understand genetic diversity and evolutionary processes within populations.

Genetic polymorphism refers to the occurrence of multiple forms (called alleles) of a particular gene within a population. These variations in the DNA sequence do not generally affect the function or survival of the organism, but they can contribute to differences in traits among individuals. Genetic polymorphisms can be caused by single nucleotide changes (SNPs), insertions or deletions of DNA segments, or other types of genetic rearrangements. They are important for understanding genetic diversity and evolution, as well as for identifying genetic factors that may contribute to disease susceptibility in humans.

Single Nucleotide Polymorphism (SNP) is a type of genetic variation that occurs when a single nucleotide (A, T, C, or G) in the DNA sequence is altered. This alteration must occur in at least 1% of the population to be considered a SNP. These variations can help explain why some people are more susceptible to certain diseases than others and can also influence how an individual responds to certain medications. SNPs can serve as biological markers, helping scientists locate genes that are associated with disease. They can also provide information about an individual's ancestry and ethnic background.

A mutation is a permanent change in the DNA sequence of an organism's genome. Mutations can occur spontaneously or be caused by environmental factors such as exposure to radiation, chemicals, or viruses. They may have various effects on the organism, ranging from benign to harmful, depending on where they occur and whether they alter the function of essential proteins. In some cases, mutations can increase an individual's susceptibility to certain diseases or disorders, while in others, they may confer a survival advantage. Mutations are the driving force behind evolution, as they introduce new genetic variability into populations, which can then be acted upon by natural selection.

Genetic predisposition to disease refers to an increased susceptibility or vulnerability to develop a particular illness or condition due to inheriting specific genetic variations or mutations from one's parents. These genetic factors can make it more likely for an individual to develop a certain disease, but it does not guarantee that the person will definitely get the disease. Environmental factors, lifestyle choices, and interactions between genes also play crucial roles in determining if a genetically predisposed person will actually develop the disease. It is essential to understand that having a genetic predisposition only implies a higher risk, not an inevitable outcome.

A phenotype is the physical or biochemical expression of an organism's genes, or the observable traits and characteristics resulting from the interaction of its genetic constitution (genotype) with environmental factors. These characteristics can include appearance, development, behavior, and resistance to disease, among others. Phenotypes can vary widely, even among individuals with identical genotypes, due to differences in environmental influences, gene expression, and genetic interactions.

A haplotype is a group of genes or DNA sequences that are inherited together from a single parent. It refers to a combination of alleles (variant forms of a gene) that are located on the same chromosome and are usually transmitted as a unit. Haplotypes can be useful in tracing genetic ancestry, understanding the genetic basis of diseases, and developing personalized medical treatments.

In population genetics, haplotypes are often used to study patterns of genetic variation within and between populations. By comparing haplotype frequencies across populations, researchers can infer historical events such as migrations, population expansions, and bottlenecks. Additionally, haplotypes can provide information about the evolutionary history of genes and genomic regions.

In clinical genetics, haplotypes can be used to identify genetic risk factors for diseases or to predict an individual's response to certain medications. For example, specific haplotypes in the HLA gene region have been associated with increased susceptibility to certain autoimmune diseases, while other haplotypes in the CYP450 gene family can affect how individuals metabolize drugs.

Overall, haplotypes provide a powerful tool for understanding the genetic basis of complex traits and diseases, as well as for developing personalized medical treatments based on an individual's genetic makeup.

Genetic variation refers to the differences in DNA sequences among individuals and populations. These variations can result from mutations, genetic recombination, or gene flow between populations. Genetic variation is essential for evolution by providing the raw material upon which natural selection acts. It can occur within a single gene, between different genes, or at larger scales, such as differences in the number of chromosomes or entire sets of chromosomes. The study of genetic variation is crucial in understanding the genetic basis of diseases and traits, as well as the evolutionary history and relationships among species.

A heterozygote is an individual who has inherited two different alleles (versions) of a particular gene, one from each parent. This means that the individual's genotype for that gene contains both a dominant and a recessive allele. The dominant allele will be expressed phenotypically (outwardly visible), while the recessive allele may or may not have any effect on the individual's observable traits, depending on the specific gene and its function. Heterozygotes are often represented as 'Aa', where 'A' is the dominant allele and 'a' is the recessive allele.

Molecular sequence data refers to the specific arrangement of molecules, most commonly nucleotides in DNA or RNA, or amino acids in proteins, that make up a biological macromolecule. This data is generated through laboratory techniques such as sequencing, and provides information about the exact order of the constituent molecules. This data is crucial in various fields of biology, including genetics, evolution, and molecular biology, allowing for comparisons between different organisms, identification of genetic variations, and studies of gene function and regulation.

A homozygote is an individual who has inherited the same allele (version of a gene) from both parents and therefore possesses two identical copies of that allele at a specific genetic locus. This can result in either having two dominant alleles (homozygous dominant) or two recessive alleles (homozygous recessive). In contrast, a heterozygote has inherited different alleles from each parent for a particular gene.

The term "homozygote" is used in genetics to describe the genetic makeup of an individual at a specific locus on their chromosomes. Homozygosity can play a significant role in determining an individual's phenotype (observable traits), as having two identical alleles can strengthen the expression of certain characteristics compared to having just one dominant and one recessive allele.

A base sequence in the context of molecular biology refers to the specific order of nucleotides in a DNA or RNA molecule. In DNA, these nucleotides are adenine (A), guanine (G), cytosine (C), and thymine (T). In RNA, uracil (U) takes the place of thymine. The base sequence contains genetic information that is transcribed into RNA and ultimately translated into proteins. It is the exact order of these bases that determines the genetic code and thus the function of the DNA or RNA molecule.

Polymerase Chain Reaction (PCR) is a laboratory technique used to amplify specific regions of DNA. It enables the production of thousands to millions of copies of a particular DNA sequence in a rapid and efficient manner, making it an essential tool in various fields such as molecular biology, medical diagnostics, forensic science, and research.

The PCR process involves repeated cycles of heating and cooling to separate the DNA strands, allow primers (short sequences of single-stranded DNA) to attach to the target regions, and extend these primers using an enzyme called Taq polymerase, resulting in the exponential amplification of the desired DNA segment.

In a medical context, PCR is often used for detecting and quantifying specific pathogens (viruses, bacteria, fungi, or parasites) in clinical samples, identifying genetic mutations or polymorphisms associated with diseases, monitoring disease progression, and evaluating treatment effectiveness.

Chromosome mapping, also known as physical mapping, is the process of determining the location and order of specific genes or genetic markers on a chromosome. This is typically done by using various laboratory techniques to identify landmarks along the chromosome, such as restriction enzyme cutting sites or patterns of DNA sequence repeats. The resulting map provides important information about the organization and structure of the genome, and can be used for a variety of purposes, including identifying the location of genes associated with genetic diseases, studying evolutionary relationships between organisms, and developing genetic markers for use in breeding or forensic applications.

Linkage disequilibrium (LD) is a term used in genetics that refers to the non-random association of alleles at different loci (genetic locations) on a chromosome. This means that certain combinations of genetic variants, or alleles, at different loci occur more frequently together in a population than would be expected by chance.

Linkage disequilibrium can arise due to various factors such as genetic drift, selection, mutation, and population structure. It is often used in the context of genetic mapping studies to identify regions of the genome that are associated with particular traits or diseases. High levels of LD in a region of the genome suggest that the loci within that region are in linkage, meaning they tend to be inherited together.

The degree of LD between two loci can be measured using various statistical methods, such as D' and r-squared. These measures provide information about the strength and direction of the association between alleles at different loci, which can help researchers identify causal genetic variants underlying complex traits or diseases.

Microsatellite repeats, also known as short tandem repeats (STRs), are repetitive DNA sequences made up of units of 1-6 base pairs that are repeated in a head-to-tail manner. These repeats are spread throughout the human genome and are highly polymorphic, meaning they can have different numbers of repeat units in different individuals.

Microsatellites are useful as genetic markers because of their high degree of variability. They are commonly used in forensic science to identify individuals, in genealogy to trace ancestry, and in medical research to study genetic diseases and disorders. Mutations in microsatellite repeats have been associated with various neurological conditions, including Huntington's disease and fragile X syndrome.

Genetic markers are specific segments of DNA that are used in genetic mapping and genotyping to identify specific genetic locations, diseases, or traits. They can be composed of short tandem repeats (STRs), single nucleotide polymorphisms (SNPs), restriction fragment length polymorphisms (RFLPs), or variable number tandem repeats (VNTRs). These markers are useful in various fields such as genetic research, medical diagnostics, forensic science, and breeding programs. They can help to track inheritance patterns, identify genetic predispositions to diseases, and solve crimes by linking biological evidence to suspects or victims.

A case-control study is an observational research design used to identify risk factors or causes of a disease or health outcome. In this type of study, individuals with the disease or condition (cases) are compared with similar individuals who do not have the disease or condition (controls). The exposure history or other characteristics of interest are then compared between the two groups to determine if there is an association between the exposure and the disease.

Case-control studies are often used when it is not feasible or ethical to conduct a randomized controlled trial, as they can provide valuable insights into potential causes of diseases or health outcomes in a relatively short period of time and at a lower cost than other study designs. However, because case-control studies rely on retrospective data collection, they are subject to biases such as recall bias and selection bias, which can affect the validity of the results. Therefore, it is important to carefully design and conduct case-control studies to minimize these potential sources of bias.

HLA-DRB1 chains are part of the major histocompatibility complex (MHC) class II molecules in the human body. The MHC class II molecules play a crucial role in the immune system by presenting pieces of foreign proteins to CD4+ T cells, which then stimulate an immune response.

HLA-DRB1 chains are one of the two polypeptide chains that make up the HLA-DR heterodimer, the other chain being the HLA-DRA chain. The HLA-DRB1 chain contains specific regions called antigen-binding sites, which bind to and present foreign peptides to CD4+ T cells.

The HLA-DRB1 gene is highly polymorphic, meaning that there are many different variations or alleles of this gene in the human population. These variations can affect an individual's susceptibility or resistance to certain diseases, including autoimmune disorders and infectious diseases. Therefore, the identification and characterization of HLA-DRB1 alleles have important implications for disease diagnosis, treatment, and prevention.

"Genetic crosses" refer to the breeding of individuals with different genetic characteristics to produce offspring with specific combinations of traits. This process is commonly used in genetics research to study the inheritance patterns and function of specific genes.

There are several types of genetic crosses, including:

1. Monohybrid cross: A cross between two individuals that differ in the expression of a single gene or trait.
2. Dihybrid cross: A cross between two individuals that differ in the expression of two genes or traits.
3. Backcross: A cross between an individual from a hybrid population and one of its parental lines.
4. Testcross: A cross between an individual with unknown genotype and a homozygous recessive individual.
5. Reciprocal cross: A cross in which the male and female parents are reversed to determine if there is any effect of sex on the expression of the trait.

These genetic crosses help researchers to understand the mode of inheritance, linkage, recombination, and other genetic phenomena.

Restriction Fragment Length Polymorphism (RFLP) is a term used in molecular biology and genetics. It refers to the presence of variations in DNA sequences among individuals, which can be detected by restriction enzymes. These enzymes cut DNA at specific sites, creating fragments of different lengths.

In RFLP analysis, DNA is isolated from an individual and treated with a specific restriction enzyme that cuts the DNA at particular recognition sites. The resulting fragments are then separated by size using gel electrophoresis, creating a pattern unique to that individual's DNA. If there are variations in the DNA sequence between individuals, the restriction enzyme may cut the DNA at different sites, leading to differences in the length of the fragments and thus, a different pattern on the gel.

These variations can be used for various purposes, such as identifying individuals, diagnosing genetic diseases, or studying evolutionary relationships between species. However, RFLP analysis has largely been replaced by more modern techniques like polymerase chain reaction (PCR)-based methods and DNA sequencing, which offer higher resolution and throughput.

Genetic models are theoretical frameworks used in genetics to describe and explain the inheritance patterns and genetic architecture of traits, diseases, or phenomena. These models are based on mathematical equations and statistical methods that incorporate information about gene frequencies, modes of inheritance, and the effects of environmental factors. They can be used to predict the probability of certain genetic outcomes, to understand the genetic basis of complex traits, and to inform medical management and treatment decisions.

There are several types of genetic models, including:

1. Mendelian models: These models describe the inheritance patterns of simple genetic traits that follow Mendel's laws of segregation and independent assortment. Examples include autosomal dominant, autosomal recessive, and X-linked inheritance.
2. Complex trait models: These models describe the inheritance patterns of complex traits that are influenced by multiple genes and environmental factors. Examples include heart disease, diabetes, and cancer.
3. Population genetics models: These models describe the distribution and frequency of genetic variants within populations over time. They can be used to study evolutionary processes, such as natural selection and genetic drift.
4. Quantitative genetics models: These models describe the relationship between genetic variation and phenotypic variation in continuous traits, such as height or IQ. They can be used to estimate heritability and to identify quantitative trait loci (QTLs) that contribute to trait variation.
5. Statistical genetics models: These models use statistical methods to analyze genetic data and infer the presence of genetic associations or linkage. They can be used to identify genetic risk factors for diseases or traits.

Overall, genetic models are essential tools in genetics research and medical genetics, as they allow researchers to make predictions about genetic outcomes, test hypotheses about the genetic basis of traits and diseases, and develop strategies for prevention, diagnosis, and treatment.

Population Genetics is a subfield of genetics that deals with the genetic composition of populations and how this composition changes over time. It involves the study of the frequency and distribution of genes and genetic variations in populations, as well as the evolutionary forces that contribute to these patterns, such as mutation, gene flow, genetic drift, and natural selection.

Population genetics can provide insights into a wide range of topics, including the history and relationships between populations, the genetic basis of diseases and other traits, and the potential impacts of environmental changes on genetic diversity. This field is important for understanding evolutionary processes at the population level and has applications in areas such as conservation biology, medical genetics, and forensic science.

DNA Sequence Analysis is the systematic determination of the order of nucleotides in a DNA molecule. It is a critical component of modern molecular biology, genetics, and genetic engineering. The process involves determining the exact order of the four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - in a DNA molecule or fragment. This information is used in various applications such as identifying gene mutations, studying evolutionary relationships, developing molecular markers for breeding, and diagnosing genetic diseases.

The process of DNA Sequence Analysis typically involves several steps, including DNA extraction, PCR amplification (if necessary), purification, sequencing reaction, and electrophoresis. The resulting data is then analyzed using specialized software to determine the exact sequence of nucleotides.

In recent years, high-throughput DNA sequencing technologies have revolutionized the field of genomics, enabling the rapid and cost-effective sequencing of entire genomes. This has led to an explosion of genomic data and new insights into the genetic basis of many diseases and traits.

An amino acid sequence is the specific order of amino acids in a protein or peptide molecule, formed by the linking of the amino group (-NH2) of one amino acid to the carboxyl group (-COOH) of another amino acid through a peptide bond. The sequence is determined by the genetic code and is unique to each type of protein or peptide. It plays a crucial role in determining the three-dimensional structure and function of proteins.

I must clarify that the term "pedigree" is not typically used in medical definitions. Instead, it is often employed in genetics and breeding, where it refers to the recorded ancestry of an individual or a family, tracing the inheritance of specific traits or diseases. In human genetics, a pedigree can help illustrate the pattern of genetic inheritance in families over multiple generations. However, it is not a medical term with a specific clinical definition.

Genetic linkage is the phenomenon where two or more genetic loci (locations on a chromosome) tend to be inherited together because they are close to each other on the same chromosome. This occurs during the process of sexual reproduction, where homologous chromosomes pair up and exchange genetic material through a process called crossing over.

The closer two loci are to each other on a chromosome, the lower the probability that they will be separated by a crossover event. As a result, they are more likely to be inherited together and are said to be linked. The degree of linkage between two loci can be measured by their recombination frequency, which is the percentage of meiotic events in which a crossover occurs between them.

Linkage analysis is an important tool in genetic research, as it allows researchers to identify and map genes that are associated with specific traits or diseases. By analyzing patterns of linkage between markers (identifiable DNA sequences) and phenotypes (observable traits), researchers can infer the location of genes that contribute to those traits or diseases on chromosomes.

Genetic association studies are a type of epidemiological research that aims to identify statistical associations between genetic variations and particular traits or diseases. These studies typically compare the frequency of specific genetic markers, such as single nucleotide polymorphisms (SNPs), in individuals with a given trait or disease to those without it.

The goal of genetic association studies is to identify genetic factors that contribute to the risk of developing common complex diseases, such as diabetes, heart disease, or cancer. By identifying these genetic associations, researchers hope to gain insights into the underlying biological mechanisms of these diseases and develop new strategies for prevention, diagnosis, and treatment.

It's important to note that while genetic association studies can identify statistical associations between genetic markers and traits or diseases, they cannot prove causality. Further research is needed to confirm and validate these findings and to understand the functional consequences of the identified genetic variants.

The term "Asian Continental Ancestry Group" is a medical/ethnic classification used to describe a person's genetic background and ancestry. According to this categorization, individuals with origins in the Asian continent are grouped together. This includes populations from regions such as East Asia (e.g., China, Japan, Korea), South Asia (e.g., India, Pakistan, Bangladesh), Southeast Asia (e.g., Philippines, Indonesia, Thailand), and Central Asia (e.g., Kazakhstan, Uzbekistan, Tajikistan). It is important to note that this broad categorization may not fully capture the genetic diversity within these regions or accurately reflect an individual's specific ancestral origins.

Exons are the coding regions of DNA that remain in the mature, processed mRNA after the removal of non-coding intronic sequences during RNA splicing. These exons contain the information necessary to encode proteins, as they specify the sequence of amino acids within a polypeptide chain. The arrangement and order of exons can vary between different genes and even between different versions of the same gene (alternative splicing), allowing for the generation of multiple protein isoforms from a single gene. This complexity in exon structure and usage significantly contributes to the diversity and functionality of the proteome.

DNA Mutational Analysis is a laboratory test used to identify genetic variations or changes (mutations) in the DNA sequence of a gene. This type of analysis can be used to diagnose genetic disorders, predict the risk of developing certain diseases, determine the most effective treatment for cancer, or assess the likelihood of passing on an inherited condition to offspring.

The test involves extracting DNA from a patient's sample (such as blood, saliva, or tissue), amplifying specific regions of interest using polymerase chain reaction (PCR), and then sequencing those regions to determine the precise order of nucleotide bases in the DNA molecule. The resulting sequence is then compared to reference sequences to identify any variations or mutations that may be present.

DNA Mutational Analysis can detect a wide range of genetic changes, including single-nucleotide polymorphisms (SNPs), insertions, deletions, duplications, and rearrangements. The test is often used in conjunction with other diagnostic tests and clinical evaluations to provide a comprehensive assessment of a patient's genetic profile.

It is important to note that not all mutations are pathogenic or associated with disease, and the interpretation of DNA Mutational Analysis results requires careful consideration of the patient's medical history, family history, and other relevant factors.

DNA primers are short single-stranded DNA molecules that serve as a starting point for DNA synthesis. They are typically used in laboratory techniques such as the polymerase chain reaction (PCR) and DNA sequencing. The primer binds to a complementary sequence on the DNA template through base pairing, providing a free 3'-hydroxyl group for the DNA polymerase enzyme to add nucleotides and synthesize a new strand of DNA. This allows for specific and targeted amplification or analysis of a particular region of interest within a larger DNA molecule.

HLA-DQ antigens are a type of human leukocyte antigen (HLA) that are found on the surface of cells in our body. They are a part of the major histocompatibility complex (MHC) class II molecules, which play a crucial role in the immune system by presenting pieces of proteins from outside the cell to CD4+ T cells, also known as helper T cells. This presentation process is essential for initiating an appropriate immune response against potentially harmful pathogens such as bacteria and viruses.

HLA-DQ antigens are encoded by genes located on chromosome 6p21.3 in the HLA region. Each individual inherits a pair of HLA-DQ genes, one from each parent, which can result in various combinations of HLA-DQ alleles. These genetic variations contribute to the diversity of immune responses among different individuals.

HLA-DQ antigens consist of two noncovalently associated polypeptide chains: an alpha (DQA) chain and a beta (DQB) chain. There are several isotypes of HLA-DQ antigens, including DQ1, DQ2, DQ3, DQ4, DQ5, DQ6, DQ7, DQ8, and DQ9, which are determined by the specific combination of DQA and DQB alleles.

Certain HLA-DQ genotypes have been associated with an increased risk of developing certain autoimmune diseases, such as celiac disease (DQ2 and DQ8), type 1 diabetes (DQ2, DQ8), and rheumatoid arthritis (DQ4). Understanding the role of HLA-DQ antigens in these conditions can provide valuable insights into disease pathogenesis and potential therapeutic targets.

HLA-DR antigens are a type of human leukocyte antigen (HLA) class II molecule that plays a crucial role in the immune system. They are found on the surface of antigen-presenting cells, such as dendritic cells, macrophages, and B lymphocytes. HLA-DR molecules present peptide antigens to CD4+ T cells, also known as helper T cells, thereby initiating an immune response.

HLA-DR antigens are highly polymorphic, meaning that there are many different variants of these molecules in the human population. This diversity allows for a wide range of potential peptide antigens to be presented and recognized by the immune system. HLA-DR antigens are encoded by genes located on chromosome 6 in the major histocompatibility complex (MHC) region.

In transplantation, HLA-DR compatibility between donor and recipient is an important factor in determining the success of the transplant. Incompatibility can lead to a heightened immune response against the transplanted organ or tissue, resulting in rejection. Additionally, certain HLA-DR types have been associated with increased susceptibility to autoimmune diseases, such as rheumatoid arthritis and multiple sclerosis.

A lethal gene is a type of gene that causes the death of an organism or prevents it from surviving to maturity. This can occur when the gene contains a mutation that disrupts the function of a protein essential for the organism's survival. In some cases, the presence of two copies of a lethal gene (one inherited from each parent) can result in a condition that is incompatible with life, and the organism will not survive beyond embryonic development or shortly after birth.

Lethal genes can also contribute to genetic disorders, where the disruption of protein function caused by the mutation leads to progressive degeneration and ultimately death. In some cases, lethal genes may only cause harm when expressed in certain tissues or at specific stages of development, leading to a range of phenotypes from embryonic lethality to adult-onset disorders.

It's important to note that the term "lethal" is relative and can depend on various factors such as genetic background, environmental conditions, and the presence of modifier genes. Additionally, some lethal genes may be targeted for gene editing or other therapeutic interventions to prevent their harmful effects.

Genetic selection, also known as natural selection, is a fundamental mechanism of evolution. It refers to the process by which certain heritable traits become more or less common in a population over successive generations due to differential reproduction of organisms with those traits.

In genetic selection, traits that increase an individual's fitness (its ability to survive and reproduce) are more likely to be passed on to the next generation, while traits that decrease fitness are less likely to be passed on. This results in a gradual change in the distribution of traits within a population over time, leading to adaptation to the environment and potentially speciation.

Genetic selection can occur through various mechanisms, including viability selection (differential survival), fecundity selection (differences in reproductive success), and sexual selection (choices made by individuals during mating). The process of genetic selection is driven by environmental pressures, such as predation, competition for resources, and changes in the availability of food or habitat.

A genetic locus (plural: loci) is a specific location on a chromosome where a particular gene or DNA sequence is found. It is the precise position where a specific genetic element, such as a gene or marker, is located on a chromsomere. This location is defined in terms of its relationship to other genetic markers and features on the same chromosome. Genetic loci can be used in linkage and association studies to identify the inheritance patterns and potential relationships between genes and various traits or diseases.

Dominant genes refer to the alleles (versions of a gene) that are fully expressed in an individual's phenotype, even if only one copy of the gene is present. In dominant inheritance patterns, an individual needs only to receive one dominant allele from either parent to express the associated trait. This is in contrast to recessive genes, where both copies of the gene must be the recessive allele for the trait to be expressed. Dominant genes are represented by uppercase letters (e.g., 'A') and recessive genes by lowercase letters (e.g., 'a'). If an individual inherits one dominant allele (A) from either parent, they will express the dominant trait (A).

The term "European Continental Ancestry Group" is a medical/ethnic classification that refers to individuals who trace their genetic ancestry to the continent of Europe. This group includes people from various ethnic backgrounds and nationalities, such as Northern, Southern, Eastern, and Western European descent. It is often used in research and medical settings for population studies or to identify genetic patterns and predispositions to certain diseases that may be more common in specific ancestral groups. However, it's important to note that this classification can oversimplify the complex genetic diversity within and between populations, and should be used with caution.

HLA-B antigens are human leukocyte antigen (HLA) proteins found on the surface of cells that play an important role in the body's immune system. They are part of the major histocompatibility complex (MHC) class I molecules, which present pieces of proteins from inside the cell to T-cells, a type of white blood cell involved in immune responses.

HLA-B antigens are highly polymorphic, meaning that there are many different variations or alleles of this gene in the human population. This genetic diversity allows for a wide range of potential HLA-B proteins to be expressed, which can help recognize and respond to a variety of foreign substances, such as viruses and cancer cells.

The HLA-B antigens are inherited from both parents, and an individual may express one or two different HLA-B antigens depending on their genetic makeup. The specific combination of HLA-B antigens that a person expresses can have implications for their susceptibility to certain diseases, as well as their compatibility with organ transplants.

Recessive genes refer to the alleles (versions of a gene) that will only be expressed when an individual has two copies of that particular allele, one inherited from each parent. If an individual inherits one recessive allele and one dominant allele for a particular gene, the dominant allele will be expressed and the recessive allele will have no effect on the individual's phenotype (observable traits).

Recessive genes can still play a role in determining an individual's genetic makeup and can be passed down through generations even if they are not expressed. If two carriers of a recessive gene have children, there is a 25% chance that their offspring will inherit two copies of the recessive allele and exhibit the associated recessive trait.

Examples of genetic disorders caused by recessive genes include cystic fibrosis, sickle cell anemia, and albinism.

Apolipoprotein E (APOE) is a gene that provides instructions for making a protein involved in the metabolism of fats called lipids. One variant of this gene, APOE4, is associated with an increased risk of developing Alzheimer's disease and other forms of dementia.

The APOE4 allele (variant) is less efficient at clearing beta-amyloid protein, a component of the amyloid plaques found in the brains of people with Alzheimer's disease. This can lead to an accumulation of beta-amyloid and an increased risk of developing Alzheimer's disease.

It is important to note that having one or two copies of the APOE4 allele does not mean that a person will definitely develop Alzheimer's disease, but it does increase the risk. Other factors, such as age, family history, and the presence of other genetic variants, also contribute to the development of this complex disorder.

Genetic suppression is a concept in genetics that refers to the phenomenon where the expression or function of one gene is reduced or silenced by another gene. This can occur through various mechanisms such as:

* Allelic exclusion: When only one allele (version) of a gene is expressed, while the other is suppressed.
* Epigenetic modifications: Chemical changes to the DNA or histone proteins that package DNA can result in the suppression of gene expression.
* RNA interference: Small RNAs can bind to and degrade specific mRNAs (messenger RNAs), preventing their translation into proteins.
* Transcriptional repression: Proteins called transcription factors can bind to DNA and prevent the recruitment of RNA polymerase, which is necessary for gene transcription.

Genetic suppression plays a crucial role in regulating gene expression and maintaining proper cellular function. It can also contribute to diseases such as cancer when genes that suppress tumor growth are suppressed themselves.

A point mutation is a type of genetic mutation where a single nucleotide base (A, T, C, or G) in DNA is altered, deleted, or substituted with another nucleotide. Point mutations can have various effects on the organism, depending on the location of the mutation and whether it affects the function of any genes. Some point mutations may not have any noticeable effect, while others might lead to changes in the amino acids that make up proteins, potentially causing diseases or altering traits. Point mutations can occur spontaneously due to errors during DNA replication or be inherited from parents.

Deoxyribonucleic acid (DNA) is the genetic material present in the cells of organisms where it is responsible for the storage and transmission of hereditary information. DNA is a long molecule that consists of two strands coiled together to form a double helix. Each strand is made up of a series of four nucleotide bases - adenine (A), guanine (G), cytosine (C), and thymine (T) - that are linked together by phosphate and sugar groups. The sequence of these bases along the length of the molecule encodes genetic information, with A always pairing with T and C always pairing with G. This base-pairing allows for the replication and transcription of DNA, which are essential processes in the functioning and reproduction of all living organisms.

Genetic recombination is the process by which genetic material is exchanged between two similar or identical molecules of DNA during meiosis, resulting in new combinations of genes on each chromosome. This exchange occurs during crossover, where segments of DNA are swapped between non-sister homologous chromatids, creating genetic diversity among the offspring. It is a crucial mechanism for generating genetic variability and facilitating evolutionary change within populations. Additionally, recombination also plays an essential role in DNA repair processes through mechanisms such as homologous recombinational repair (HRR) and non-homologous end joining (NHEJ).

Minisatellites, also known as VNTRs (Variable Number Tandem Repeats), are repetitive DNA sequences that consist of a core repeat unit of 10-60 base pairs, arranged in a head-to-tail fashion. They are often found in non-coding regions of the genome and can vary in the number of times the repeat unit is present in an individual's DNA. This variation in repeat number can occur both within and between individuals, making minisatellites useful as genetic markers for identification and forensic applications. They are also associated with certain genetic disorders and play a role in genome instability.

A genetic complementation test is a laboratory procedure used in molecular genetics to determine whether two mutated genes can complement each other's function, indicating that they are located at different loci and represent separate alleles. This test involves introducing a normal or wild-type copy of one gene into a cell containing a mutant version of the same gene, and then observing whether the presence of the normal gene restores the normal function of the mutated gene. If the introduction of the normal gene results in the restoration of the normal phenotype, it suggests that the two genes are located at different loci and can complement each other's function. However, if the introduction of the normal gene does not restore the normal phenotype, it suggests that the two genes are located at the same locus and represent different alleles of the same gene. This test is commonly used to map genes and identify genetic interactions in a variety of organisms, including bacteria, yeast, and animals.

Heterozygote detection is a method used in genetics to identify individuals who carry one normal and one mutated copy of a gene. These individuals are known as heterozygotes and they do not typically show symptoms of the genetic disorder associated with the mutation, but they can pass the mutated gene on to their offspring, who may then be affected.

Heterozygote detection is often used in genetic counseling and screening programs for recessive disorders such as cystic fibrosis or sickle cell anemia. By identifying heterozygotes, individuals can be informed of their carrier status and the potential risks to their offspring. This information can help them make informed decisions about family planning and reproductive options.

Various methods can be used for heterozygote detection, including polymerase chain reaction (PCR) based tests, DNA sequencing, and genetic linkage analysis. The choice of method depends on the specific gene or mutation being tested, as well as the availability and cost of the testing technology.

Gene deletion is a type of mutation where a segment of DNA, containing one or more genes, is permanently lost or removed from a chromosome. This can occur due to various genetic mechanisms such as homologous recombination, non-homologous end joining, or other types of genomic rearrangements.

The deletion of a gene can have varying effects on the organism, depending on the function of the deleted gene and its importance for normal physiological processes. If the deleted gene is essential for survival, the deletion may result in embryonic lethality or developmental abnormalities. However, if the gene is non-essential or has redundant functions, the deletion may not have any noticeable effects on the organism's phenotype.

Gene deletions can also be used as a tool in genetic research to study the function of specific genes and their role in various biological processes. For example, researchers may use gene deletion techniques to create genetically modified animal models to investigate the impact of gene deletion on disease progression or development.

A missense mutation is a type of point mutation in which a single nucleotide change results in the substitution of a different amino acid in the protein that is encoded by the affected gene. This occurs when the altered codon (a sequence of three nucleotides that corresponds to a specific amino acid) specifies a different amino acid than the original one. The function and/or stability of the resulting protein may be affected, depending on the type and location of the missense mutation. Missense mutations can have various effects, ranging from benign to severe, depending on the importance of the changed amino acid for the protein's structure or function.

Promoter regions in genetics refer to specific DNA sequences located near the transcription start site of a gene. They serve as binding sites for RNA polymerase and various transcription factors that regulate the initiation of gene transcription. These regulatory elements help control the rate of transcription and, therefore, the level of gene expression. Promoter regions can be composed of different types of sequences, such as the TATA box and CAAT box, and their organization and composition can vary between different genes and species.

Medical Definition:

"Risk factors" are any attribute, characteristic or exposure of an individual that increases the likelihood of developing a disease or injury. They can be divided into modifiable and non-modifiable risk factors. Modifiable risk factors are those that can be changed through lifestyle choices or medical treatment, while non-modifiable risk factors are inherent traits such as age, gender, or genetic predisposition. Examples of modifiable risk factors include smoking, alcohol consumption, physical inactivity, and unhealthy diet, while non-modifiable risk factors include age, sex, and family history. It is important to note that having a risk factor does not guarantee that a person will develop the disease, but rather indicates an increased susceptibility.

Quantitative Trait Loci (QTL) are regions of the genome that are associated with variation in quantitative traits, which are traits that vary continuously in a population and are influenced by multiple genes and environmental factors. QTLs can help to explain how genetic variations contribute to differences in complex traits such as height, blood pressure, or disease susceptibility.

Quantitative trait loci are identified through statistical analysis of genetic markers and trait values in experimental crosses between genetically distinct individuals, such as strains of mice or plants. The location of a QTL is inferred based on the pattern of linkage disequilibrium between genetic markers and the trait of interest. Once a QTL has been identified, further analysis can be conducted to identify the specific gene or genes responsible for the variation in the trait.

It's important to note that QTLs are not themselves genes, but rather genomic regions that contain one or more genes that contribute to the variation in a quantitative trait. Additionally, because QTLs are identified through statistical analysis, they represent probabilistic estimates of the location of genetic factors influencing a trait and may encompass large genomic regions containing multiple genes. Therefore, additional research is often required to fine-map and identify the specific genes responsible for the variation in the trait.

A Genome-Wide Association Study (GWAS) is an analytical approach used in genetic research to identify associations between genetic variants, typically Single Nucleotide Polymorphisms (SNPs), and specific traits or diseases across the entire genome. This method involves scanning the genomes of many individuals, usually thousands, to find genetic markers that occur more frequently in people with a particular disease or trait than in those without it.

The goal of a GWAS is to identify genetic loci (positions on chromosomes) associated with a trait or disease, which can help researchers understand the underlying genetic architecture and biological mechanisms contributing to the condition. It's important to note that while GWAS can identify associations between genetic variants and traits/diseases, these studies do not necessarily prove causation. Further functional validation studies are often required to confirm the role of identified genetic variants in the development or progression of a trait or disease.

HLA-DQ alpha-chains are a type of human leukocyte antigen (HLA) class II molecule found on the surface of various cells in the body, including immune cells such as B lymphocytes and dendritic cells. HLAs play a critical role in the immune system by presenting pieces of proteins from inside the cell to T-cells, which are responsible for mounting an immune response against potentially harmful pathogens or abnormal cells.

The HLA-DQ alpha-chain is one component of the HLA-DQ heterodimer, which also includes a beta-chain. Together, these two chains form a functional HLA-DQ molecule that can bind and present peptides to CD4+ T-cells (also known as helper T-cells). The HLA-DQ complex is involved in the immune response to various pathogens, including bacteria, viruses, and parasites.

Polymorphisms (variations) in the genes encoding HLA-DQ alpha-chains can contribute to differences in individual susceptibility to certain autoimmune diseases, such as type 1 diabetes, celiac disease, and rheumatoid arthritis. Additionally, specific HLA-DQ genotypes have been associated with increased or decreased risk for these conditions.

Introns are non-coding sequences of DNA that are present within the genes of eukaryotic organisms, including plants, animals, and humans. Introns are removed during the process of RNA splicing, in which the initial RNA transcript is cut and reconnected to form a mature, functional RNA molecule.

After the intron sequences are removed, the remaining coding sequences, known as exons, are joined together to create a continuous stretch of genetic information that can be translated into a protein or used to produce non-coding RNAs with specific functions. The removal of introns allows for greater flexibility in gene expression and regulation, enabling the generation of multiple proteins from a single gene through alternative splicing.

In summary, introns are non-coding DNA sequences within genes that are removed during RNA processing to create functional RNA molecules or proteins.

Molecular cloning is a laboratory technique used to create multiple copies of a specific DNA sequence. This process involves several steps:

1. Isolation: The first step in molecular cloning is to isolate the DNA sequence of interest from the rest of the genomic DNA. This can be done using various methods such as PCR (polymerase chain reaction), restriction enzymes, or hybridization.
2. Vector construction: Once the DNA sequence of interest has been isolated, it must be inserted into a vector, which is a small circular DNA molecule that can replicate independently in a host cell. Common vectors used in molecular cloning include plasmids and phages.
3. Transformation: The constructed vector is then introduced into a host cell, usually a bacterial or yeast cell, through a process called transformation. This can be done using various methods such as electroporation or chemical transformation.
4. Selection: After transformation, the host cells are grown in selective media that allow only those cells containing the vector to grow. This ensures that the DNA sequence of interest has been successfully cloned into the vector.
5. Amplification: Once the host cells have been selected, they can be grown in large quantities to amplify the number of copies of the cloned DNA sequence.

Molecular cloning is a powerful tool in molecular biology and has numerous applications, including the production of recombinant proteins, gene therapy, functional analysis of genes, and genetic engineering.

A gene in plants, like in other organisms, is a hereditary unit that carries genetic information from one generation to the next. It is a segment of DNA (deoxyribonucleic acid) that contains the instructions for the development and function of an organism. Genes in plants determine various traits such as flower color, plant height, resistance to diseases, and many others. They are responsible for encoding proteins and RNA molecules that play crucial roles in the growth, development, and reproduction of plants. Plant genes can be manipulated through traditional breeding methods or genetic engineering techniques to improve crop yield, enhance disease resistance, and increase nutritional value.

"Saccharomyces cerevisiae" is not typically considered a medical term, but it is a scientific name used in the field of microbiology. It refers to a species of yeast that is commonly used in various industrial processes, such as baking and brewing. It's also widely used in scientific research due to its genetic tractability and eukaryotic cellular organization.

However, it does have some relevance to medical fields like medicine and nutrition. For example, certain strains of S. cerevisiae are used as probiotics, which can provide health benefits when consumed. They may help support gut health, enhance the immune system, and even assist in the digestion of certain nutrients.

In summary, "Saccharomyces cerevisiae" is a species of yeast with various industrial and potential medical applications.

Epistasis is a phenomenon in genetics where the effect of one gene (the "epistatic" gene) is modified by one or more other genes (the "modifier" genes). This interaction can result in different phenotypic expressions than what would be expected based on the individual effects of each gene.

In other words, epistasis occurs when the expression of one gene is influenced by the presence or absence of another gene. The gene that is being masked or modified is referred to as the hypostatic gene, while the gene doing the masking or modifying is called the epistatic gene.

Epistasis can take many forms and can be involved in complex genetic traits and diseases. It can also make it more difficult to map genes associated with certain traits or conditions because the phenotypic expression may not follow simple Mendelian inheritance patterns.

There are several types of epistasis, including recessive-recessive, dominant-recessive, and dominant-dominant epistasis. In recessive-recessive epistasis, for example, the presence of two copies of the epistatic gene prevents the expression of the hypostatic gene, even if the individual has two copies of the hypostatic gene.

Understanding epistasis is important in genetics because it can help researchers better understand the genetic basis of complex traits and diseases, as well as improve breeding programs for plants and animals.

'Drosophila melanogaster' is the scientific name for a species of fruit fly that is commonly used as a model organism in various fields of biological research, including genetics, developmental biology, and evolutionary biology. Its small size, short generation time, large number of offspring, and ease of cultivation make it an ideal subject for laboratory studies. The fruit fly's genome has been fully sequenced, and many of its genes have counterparts in the human genome, which facilitates the understanding of genetic mechanisms and their role in human health and disease.

Here is a brief medical definition:

Drosophila melanogaster (droh-suh-fih-luh meh-lon-guh-ster): A species of fruit fly used extensively as a model organism in genetic, developmental, and evolutionary research. Its genome has been sequenced, revealing many genes with human counterparts, making it valuable for understanding genetic mechanisms and their role in human health and disease.

Genetic testing is a type of medical test that identifies changes in chromosomes, genes, or proteins. The results of a genetic test can confirm or rule out a suspected genetic condition or help determine a person's chance of developing or passing on a genetic disorder. Genetic tests are performed on a sample of blood, hair, skin, amniotic fluid (the fluid that surrounds a fetus during pregnancy), or other tissue. For example, a physician may recommend genetic testing to help diagnose a genetic condition, confirm the presence of a gene mutation known to increase the risk of developing certain cancers, or determine the chance for a couple to have a child with a genetic disorder.

There are several types of genetic tests, including:

* Diagnostic testing: This type of test is used to identify or confirm a suspected genetic condition in an individual. It may be performed before birth (prenatal testing) or at any time during a person's life.
* Predictive testing: This type of test is used to determine the likelihood that a person will develop a genetic disorder. It is typically offered to individuals who have a family history of a genetic condition but do not show any symptoms themselves.
* Carrier testing: This type of test is used to determine whether a person carries a gene mutation for a genetic disorder. It is often offered to couples who are planning to have children and have a family history of a genetic condition or belong to a population that has an increased risk of certain genetic disorders.
* Preimplantation genetic testing: This type of test is used in conjunction with in vitro fertilization (IVF) to identify genetic changes in embryos before they are implanted in the uterus. It can help couples who have a family history of a genetic disorder or who are at risk of having a child with a genetic condition to conceive a child who is free of the genetic change in question.
* Pharmacogenetic testing: This type of test is used to determine how an individual's genes may affect their response to certain medications. It can help healthcare providers choose the most effective medication and dosage for a patient, reducing the risk of adverse drug reactions.

It is important to note that genetic testing should be performed under the guidance of a qualified healthcare professional who can interpret the results and provide appropriate counseling and support.

HLA (Human Leukocyte Antigen) antigens are a group of proteins found on the surface of cells in our body. They play a crucial role in the immune system's ability to differentiate between "self" and "non-self." HLA antigens are encoded by a group of genes located on chromosome 6, known as the major histocompatibility complex (MHC).

There are three types of HLA antigens: HLA class I, HLA class II, and HLA class III. HLA class I antigens are found on the surface of almost all cells in the body and help the immune system recognize and destroy virus-infected or cancerous cells. They consist of three components: HLA-A, HLA-B, and HLA-C.

HLA class II antigens are primarily found on the surface of immune cells, such as macrophages, B cells, and dendritic cells. They assist in the presentation of foreign particles (like bacteria and viruses) to CD4+ T cells, which then activate other parts of the immune system. HLA class II antigens include HLA-DP, HLA-DQ, and HLA-DR.

HLA class III antigens consist of various molecules involved in immune responses, such as cytokines and complement components. They are not directly related to antigen presentation.

The genetic diversity of HLA antigens is extensive, with thousands of variations or alleles. This diversity allows for a better ability to recognize and respond to a wide range of pathogens. However, this variation can also lead to compatibility issues in organ transplantation, as the recipient's immune system may recognize the donor's HLA antigens as foreign and attack the transplanted organ.

Apolipoprotein E (ApoE) is a protein involved in the metabolism of lipids, particularly cholesterol. It is produced primarily by the liver and is a component of several types of lipoproteins, including very low-density lipoproteins (VLDL) and high-density lipoproteins (HDL).

ApoE plays a crucial role in the transport and uptake of lipids in the body. It binds to specific receptors on cell surfaces, facilitating the delivery of lipids to cells for energy metabolism or storage. ApoE also helps to clear cholesterol from the bloodstream and is involved in the repair and maintenance of tissues.

There are three major isoforms of ApoE, designated ApoE2, ApoE3, and ApoE4, which differ from each other by only a few amino acids. These genetic variations can have significant effects on an individual's risk for developing certain diseases, particularly cardiovascular disease and Alzheimer's disease. For example, individuals who inherit the ApoE4 allele have an increased risk of developing Alzheimer's disease, while those with the ApoE2 allele may have a reduced risk.

In summary, Apolipoprotein E is a protein involved in lipid metabolism and transport, and genetic variations in this protein can influence an individual's risk for certain diseases.

Fungal genes refer to the genetic material present in fungi, which are eukaryotic organisms that include microorganisms such as yeasts and molds, as well as larger organisms like mushrooms. The genetic material of fungi is composed of DNA, just like in other eukaryotes, and is organized into chromosomes located in the nucleus of the cell.

Fungal genes are segments of DNA that contain the information necessary to produce proteins and RNA molecules required for various cellular functions. These genes are transcribed into messenger RNA (mRNA) molecules, which are then translated into proteins by ribosomes in the cytoplasm.

Fungal genomes have been sequenced for many species, revealing a diverse range of genes that encode proteins involved in various cellular processes such as metabolism, signaling, and regulation. Comparative genomic analyses have also provided insights into the evolutionary relationships among different fungal lineages and have helped to identify unique genetic features that distinguish fungi from other eukaryotes.

Understanding fungal genes and their functions is essential for advancing our knowledge of fungal biology, as well as for developing new strategies to control fungal pathogens that can cause diseases in humans, animals, and plants.

Phylogeny is the evolutionary history and relationship among biological entities, such as species or genes, based on their shared characteristics. In other words, it refers to the branching pattern of evolution that shows how various organisms have descended from a common ancestor over time. Phylogenetic analysis involves constructing a tree-like diagram called a phylogenetic tree, which depicts the inferred evolutionary relationships among organisms or genes based on molecular sequence data or other types of characters. This information is crucial for understanding the diversity and distribution of life on Earth, as well as for studying the emergence and spread of diseases.

Mutagenesis is the process by which the genetic material (DNA or RNA) of an organism is changed in a way that can alter its phenotype, or observable traits. These changes, known as mutations, can be caused by various factors such as chemicals, radiation, or viruses. Some mutations may have no effect on the organism, while others can cause harm, including diseases and cancer. Mutagenesis is a crucial area of study in genetics and molecular biology, with implications for understanding evolution, genetic disorders, and the development of new medical treatments.

I am not aware of a specific medical definition for the term "China." Generally, it is used to refer to:

1. The People's Republic of China (PRC), which is a country in East Asia. It is the most populous country in the world and the fourth largest by geographical area. Its capital city is Beijing.
2. In a historical context, "China" was used to refer to various dynasties and empires that existed in East Asia over thousands of years. The term "Middle Kingdom" or "Zhongguo" (中国) has been used by the Chinese people to refer to their country for centuries.
3. In a more general sense, "China" can also be used to describe products or goods that originate from or are associated with the People's Republic of China.

If you have a specific context in which you encountered the term "China" related to medicine, please provide it so I can give a more accurate response.

Molecular evolution is the process of change in the DNA sequence or protein structure over time, driven by mechanisms such as mutation, genetic drift, gene flow, and natural selection. It refers to the evolutionary study of changes in DNA, RNA, and proteins, and how these changes accumulate and lead to new species and diversity of life. Molecular evolution can be used to understand the history and relationships among different organisms, as well as the functional consequences of genetic changes.

HLA-A antigens are a type of human leukocyte antigen (HLA) found on the surface of cells in our body. They are proteins that play an important role in the immune system by helping the body recognize and distinguish its own cells from foreign substances such as viruses, bacteria, and transplanted organs.

The HLA-A antigens are part of the major histocompatibility complex (MHC) class I molecules, which present peptide fragments from inside the cell to CD8+ T cells, also known as cytotoxic T lymphocytes (CTLs). The CTLs then recognize and destroy any cells that display foreign or abnormal peptides on their HLA-A antigens.

Each person has a unique set of HLA-A antigens, which are inherited from their parents. These antigens can vary widely between individuals, making it important to match HLA types in organ transplantation to reduce the risk of rejection. Additionally, certain HLA-A antigens have been associated with increased susceptibility or resistance to various diseases, including autoimmune disorders and infectious diseases.

The term "African Continental Ancestry Group" is a racial category used in the field of genetics and population health to describe individuals who have ancestral origins in the African continent. This group includes people from diverse ethnic backgrounds, cultures, and languages across the African continent. It's important to note that this term is used for genetic and epidemiological research purposes and should not be used to make assumptions about an individual's personal identity, culture, or experiences.

It's also worth noting that there is significant genetic diversity within Africa, and using a single category to describe all individuals with African ancestry can oversimplify this diversity. Therefore, it's more accurate and informative to specify the particular population or region of African ancestry when discussing genetic research or health outcomes.

A gene is a specific sequence of nucleotides in DNA that carries genetic information. Genes are the fundamental units of heredity and are responsible for the development and function of all living organisms. They code for proteins or RNA molecules, which carry out various functions within cells and are essential for the structure, function, and regulation of the body's tissues and organs.

Each gene has a specific location on a chromosome, and each person inherits two copies of every gene, one from each parent. Variations in the sequence of nucleotides in a gene can lead to differences in traits between individuals, including physical characteristics, susceptibility to disease, and responses to environmental factors.

Medical genetics is the study of genes and their role in health and disease. It involves understanding how genes contribute to the development and progression of various medical conditions, as well as identifying genetic risk factors and developing strategies for prevention, diagnosis, and treatment.

A sequence deletion in a genetic context refers to the removal or absence of one or more nucleotides (the building blocks of DNA or RNA) from a specific region in a DNA or RNA molecule. This type of mutation can lead to the loss of genetic information, potentially resulting in changes in the function or expression of a gene. If the deletion involves a critical portion of the gene, it can cause diseases, depending on the role of that gene in the body. The size of the deleted sequence can vary, ranging from a single nucleotide to a large segment of DNA.

Single-Stranded Conformational Polymorphism (SSCP) is not a medical condition but rather a laboratory technique used in molecular biology and genetics. It refers to the phenomenon where a single-stranded DNA or RNA molecule can adopt different conformations or shapes based on its nucleotide sequence, even if the difference in the sequence is as small as a single base pair change. This property is used in SSCP analysis to detect mutations or variations in DNA or RNA sequences.

In SSCP analysis, the denatured single-stranded DNA or RNA sample is subjected to electrophoresis on a non-denaturing polyacrylamide gel. The different conformations of the single-stranded molecules migrate at different rates in the gel, creating multiple bands that can be visualized by staining or other detection methods. The presence of additional bands or shifts in band patterns can indicate the presence of a sequence variant or mutation.

SSCP analysis is often used as a screening tool for genetic diseases, cancer, and infectious diseases to identify genetic variations associated with these conditions. However, it has largely been replaced by more sensitive and accurate methods such as next-generation sequencing.

DNA-binding proteins are a type of protein that have the ability to bind to DNA (deoxyribonucleic acid), the genetic material of organisms. These proteins play crucial roles in various biological processes, such as regulation of gene expression, DNA replication, repair and recombination.

The binding of DNA-binding proteins to specific DNA sequences is mediated by non-covalent interactions, including electrostatic, hydrogen bonding, and van der Waals forces. The specificity of binding is determined by the recognition of particular nucleotide sequences or structural features of the DNA molecule.

DNA-binding proteins can be classified into several categories based on their structure and function, such as transcription factors, histones, and restriction enzymes. Transcription factors are a major class of DNA-binding proteins that regulate gene expression by binding to specific DNA sequences in the promoter region of genes and recruiting other proteins to modulate transcription. Histones are DNA-binding proteins that package DNA into nucleosomes, the basic unit of chromatin structure. Restriction enzymes are DNA-binding proteins that recognize and cleave specific DNA sequences, and are widely used in molecular biology research and biotechnology applications.

Transcription factors are proteins that play a crucial role in regulating gene expression by controlling the transcription of DNA to messenger RNA (mRNA). They function by binding to specific DNA sequences, known as response elements, located in the promoter region or enhancer regions of target genes. This binding can either activate or repress the initiation of transcription, depending on the properties and interactions of the particular transcription factor. Transcription factors often act as part of a complex network of regulatory proteins that determine the precise spatiotemporal patterns of gene expression during development, differentiation, and homeostasis in an organism.

Dinucleotide repeats are a type of simple sequence repeat (SSR) in DNA, which consists of two adjacent nucleotides that are repeated in tandem. In the case of dinucleotide repeats, the repetitive unit is specifically a pair of nucleotides, such as "AT" or "CG." These repeats can vary in length from person to person and can be found throughout the human genome, although they are particularly prevalent in non-coding regions.

Expansions of dinucleotide repeats have been associated with several neurological disorders, including Huntington's disease, myotonic dystrophy, and fragile X syndrome. In these cases, the number of repeat units is unstable and can expand over generations, leading to the onset of disease. The length of the repeat expansion can also correlate with the severity of symptoms.

HLA-C antigens are a type of human leukocyte antigen (HLA) found on the surface of cells in the human body. They are part of the major histocompatibility complex (MHC) class I molecules, which play a critical role in the immune system's ability to differentiate between "self" and "non-self" cells.

HLA-C antigens are responsible for presenting peptide fragments from inside the cell to CD8+ T cells, also known as cytotoxic T lymphocytes (CTLs). This presentation allows the CTLs to recognize and destroy infected or damaged cells, helping to prevent the spread of viruses and other pathogens.

Like other HLA antigens, HLA-C antigens are highly polymorphic, meaning that there are many different variations of these molecules in the human population. This diversity allows for a better match between an individual's immune system and the pathogens they encounter, increasing the chances of mounting an effective immune response. However, this same diversity can also make it more challenging to find compatible organ donors for transplantation.

Insertional mutagenesis is a process of introducing new genetic material into an organism's genome at a specific location, which can result in a change or disruption of the function of the gene at that site. This technique is often used in molecular biology research to study gene function and regulation. The introduction of the foreign DNA is typically accomplished through the use of mobile genetic elements, such as transposons or viruses, which are capable of inserting themselves into the genome.

The insertion of the new genetic material can lead to a loss or gain of function in the affected gene, resulting in a mutation. This type of mutagenesis is called "insertional" because the mutation is caused by the insertion of foreign DNA into the genome. The effects of insertional mutagenesis can range from subtle changes in gene expression to the complete inactivation of a gene.

This technique has been widely used in genetic research, including the study of developmental biology, cancer, and genetic diseases. It is also used in the development of genetically modified organisms (GMOs) for agricultural and industrial applications.

A cohort study is a type of observational study in which a group of individuals who share a common characteristic or exposure are followed up over time to determine the incidence of a specific outcome or outcomes. The cohort, or group, is defined based on the exposure status (e.g., exposed vs. unexposed) and then monitored prospectively to assess for the development of new health events or conditions.

Cohort studies can be either prospective or retrospective in design. In a prospective cohort study, participants are enrolled and followed forward in time from the beginning of the study. In contrast, in a retrospective cohort study, researchers identify a cohort that has already been assembled through medical records, insurance claims, or other sources and then look back in time to assess exposure status and health outcomes.

Cohort studies are useful for establishing causality between an exposure and an outcome because they allow researchers to observe the temporal relationship between the two. They can also provide information on the incidence of a disease or condition in different populations, which can be used to inform public health policy and interventions. However, cohort studies can be expensive and time-consuming to conduct, and they may be subject to bias if participants are not representative of the population or if there is loss to follow-up.

Southern blotting is a type of membrane-based blotting technique that is used in molecular biology to detect and locate specific DNA sequences within a DNA sample. This technique is named after its inventor, Edward M. Southern.

In Southern blotting, the DNA sample is first digested with one or more restriction enzymes, which cut the DNA at specific recognition sites. The resulting DNA fragments are then separated based on their size by gel electrophoresis. After separation, the DNA fragments are denatured to convert them into single-stranded DNA and transferred onto a nitrocellulose or nylon membrane.

Once the DNA has been transferred to the membrane, it is hybridized with a labeled probe that is complementary to the sequence of interest. The probe can be labeled with radioactive isotopes, fluorescent dyes, or chemiluminescent compounds. After hybridization, the membrane is washed to remove any unbound probe and then exposed to X-ray film (in the case of radioactive probes) or scanned (in the case of non-radioactive probes) to detect the location of the labeled probe on the membrane.

The position of the labeled probe on the membrane corresponds to the location of the specific DNA sequence within the original DNA sample. Southern blotting is a powerful tool for identifying and characterizing specific DNA sequences, such as those associated with genetic diseases or gene regulation.

Gene dosage, in genetic terms, refers to the number of copies of a particular gene present in an organism's genome. Each gene usually has two copies (alleles) in diploid organisms, one inherited from each parent. An increase or decrease in the number of copies of a specific gene can lead to changes in the amount of protein it encodes, which can subsequently affect various biological processes and phenotypic traits.

For example, gene dosage imbalances have been associated with several genetic disorders, such as Down syndrome (trisomy 21), where an individual has three copies of chromosome 21 instead of the typical two copies, leading to developmental delays and intellectual disabilities. Similarly, in certain cases of cancer, gene amplification (an increase in the number of copies of a particular gene) can result in overexpression of oncogenes, contributing to tumor growth and progression.

Species specificity is a term used in the field of biology, including medicine, to refer to the characteristic of a biological entity (such as a virus, bacterium, or other microorganism) that allows it to interact exclusively or preferentially with a particular species. This means that the biological entity has a strong affinity for, or is only able to infect, a specific host species.

For example, HIV is specifically adapted to infect human cells and does not typically infect other animal species. Similarly, some bacterial toxins are species-specific and can only affect certain types of animals or humans. This concept is important in understanding the transmission dynamics and host range of various pathogens, as well as in developing targeted therapies and vaccines.

Messenger RNA (mRNA) is a type of RNA (ribonucleic acid) that carries genetic information copied from DNA in the form of a series of three-base code "words," each of which specifies a particular amino acid. This information is used by the cell's machinery to construct proteins, a process known as translation. After being transcribed from DNA, mRNA travels out of the nucleus to the ribosomes in the cytoplasm where protein synthesis occurs. Once the protein has been synthesized, the mRNA may be degraded and recycled. Post-transcriptional modifications can also occur to mRNA, such as alternative splicing and addition of a 5' cap and a poly(A) tail, which can affect its stability, localization, and translation efficiency.

Genotyping techniques are a group of laboratory methods used to identify and detect specific variations or differences in the DNA sequence, known as genetic variants or polymorphisms, that make up an individual's genotype. These techniques can be applied to various fields, including medical diagnostics, forensic science, and genetic research.

There are several types of genotyping techniques, each with its advantages and limitations depending on the application. Some common methods include:

1. Polymerase Chain Reaction (PCR)-based methods: These involve amplifying specific DNA sequences using PCR and then analyzing them for genetic variations. Examples include Restriction Fragment Length Polymorphism (RFLP), Amplification Refractory Mutation System (ARMS), and Allele-Specific PCR (AS-PCR).
2. Microarray-based methods: These involve hybridizing DNA samples to arrays containing thousands of known genetic markers or probes, allowing for simultaneous detection of multiple genetic variants. Examples include Single Nucleotide Polymorphism (SNP) arrays and Comparative Genomic Hybridization (CGH) arrays.
3. Sequencing-based methods: These involve determining the precise order of nucleotides in a DNA sequence to identify genetic variations. Examples include Sanger sequencing, Next-Generation Sequencing (NGS), and Whole Genome Sequencing (WGS).
4. Mass spectrometry-based methods: These involve measuring the mass-to-charge ratio of DNA fragments or oligonucleotides to identify genetic variants. Examples include Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF) mass spectrometry and Pyrosequencing.

Genotyping techniques have numerous applications in medicine, such as identifying genetic susceptibility to diseases, predicting drug response, and diagnosing genetic disorders. They also play a crucial role in forensic science for identifying individuals and solving crimes.

'Zea mays' is the biological name for corn or maize, which is not typically considered a medical term. However, corn or maize can have medical relevance in certain contexts. For example, cornstarch is sometimes used as a diluent for medications and is also a component of some skin products. Corn oil may be found in topical ointments and creams. In addition, some people may have allergic reactions to corn or corn-derived products. But generally speaking, 'Zea mays' itself does not have a specific medical definition.

Sequence homology, amino acid, refers to the similarity in the order of amino acids in a protein or a portion of a protein between two or more species. This similarity can be used to infer evolutionary relationships and functional similarities between proteins. The higher the degree of sequence homology, the more likely it is that the proteins are related and have similar functions. Sequence homology can be determined through various methods such as pairwise alignment or multiple sequence alignment, which compare the sequences and calculate a score based on the number and type of matching amino acids.

Fungal proteins are a type of protein that is specifically produced and present in fungi, which are a group of eukaryotic organisms that include microorganisms such as yeasts and molds. These proteins play various roles in the growth, development, and survival of fungi. They can be involved in the structure and function of fungal cells, metabolism, pathogenesis, and other cellular processes. Some fungal proteins can also have important implications for human health, both in terms of their potential use as therapeutic targets and as allergens or toxins that can cause disease.

Fungal proteins can be classified into different categories based on their functions, such as enzymes, structural proteins, signaling proteins, and toxins. Enzymes are proteins that catalyze chemical reactions in fungal cells, while structural proteins provide support and protection for the cell. Signaling proteins are involved in communication between cells and regulation of various cellular processes, and toxins are proteins that can cause harm to other organisms, including humans.

Understanding the structure and function of fungal proteins is important for developing new treatments for fungal infections, as well as for understanding the basic biology of fungi. Research on fungal proteins has led to the development of several antifungal drugs that target specific fungal enzymes or other proteins, providing effective treatment options for a range of fungal diseases. Additionally, further study of fungal proteins may reveal new targets for drug development and help improve our ability to diagnose and treat fungal infections.

Major Histocompatibility Complex (MHC) Class II genes are a group of genes that encode cell surface proteins responsible for presenting peptide antigens to CD4+ T cells, which are crucial in the adaptive immune response. These proteins are expressed mainly on professional antigen-presenting cells such as dendritic cells, macrophages, and B cells. MHC Class II molecules present extracellular antigens derived from bacteria, viruses, and other pathogens, facilitating the activation of appropriate immune responses to eliminate the threat. The genes responsible for these proteins are found within the MHC locus on chromosome 6 in humans (chromosome 17 in mice).

Trinucleotide repeats refer to a specific type of DNA sequence expansion where a particular trinucleotide (a sequence made up of three nucleotides) is repeated multiple times. In normal genomic DNA, these repeats are usually present in a relatively stable and consistent range. However, when the number of repeats exceeds a certain threshold, it can result in an unstable genetic variant known as a trinucleotide repeat expansion.

These expansions can occur in various genes and are associated with several neurogenetic disorders, such as Huntington's disease, myotonic dystrophy, fragile X syndrome, and Friedreich's ataxia. The length of the trinucleotide repeat tends to expand further in subsequent generations, which can lead to anticipation – an earlier age of onset and increased severity of symptoms in successive generations.

The most common trinucleotide repeats involve CAG (cytosine-adenine-guanine) or CTG (cytosine-thymine-guanine) repeats, although other combinations like CGG, GAA, and GCT can also be involved. These repeat expansions can result in altered gene function, protein misfolding, aggregation, and toxicity, ultimately leading to the development of neurodegenerative diseases and other clinical manifestations.

A gene suppressor, also known as a tumor suppressor gene, is a type of gene that regulates cell growth and division by producing proteins to prevent uncontrolled cell proliferation. When these genes are mutated or deleted, they can lose their ability to regulate cell growth, leading to the development of cancer.

Tumor suppressor genes work to repair damaged DNA, regulate the cell cycle, and promote programmed cell death (apoptosis) when necessary. Some examples of tumor suppressor genes include TP53, BRCA1, and BRCA2. Mutations in these genes have been linked to an increased risk of developing various types of cancer, such as breast, ovarian, and colon cancer.

In contrast to oncogenes, which promote cell growth and division when mutated, tumor suppressor genes typically act to inhibit or slow down cell growth and division. Both types of genes play crucial roles in maintaining the proper functioning of cells and preventing the development of cancer.

'Drosophila proteins' refer to the proteins that are expressed in the fruit fly, Drosophila melanogaster. This organism is a widely used model system in genetics, developmental biology, and molecular biology research. The study of Drosophila proteins has contributed significantly to our understanding of various biological processes, including gene regulation, cell signaling, development, and aging.

Some examples of well-studied Drosophila proteins include:

1. HSP70 (Heat Shock Protein 70): A chaperone protein involved in protein folding and protection from stress conditions.
2. TUBULIN: A structural protein that forms microtubules, important for cell division and intracellular transport.
3. ACTIN: A cytoskeletal protein involved in muscle contraction, cell motility, and maintenance of cell shape.
4. BETA-GALACTOSIDASE (LACZ): A reporter protein often used to monitor gene expression patterns in transgenic flies.
5. ENDOGLIN: A protein involved in the development of blood vessels during embryogenesis.
6. P53: A tumor suppressor protein that plays a crucial role in preventing cancer by regulating cell growth and division.
7. JUN-KINASE (JNK): A signaling protein involved in stress response, apoptosis, and developmental processes.
8. DECAPENTAPLEGIC (DPP): A member of the TGF-β (Transforming Growth Factor Beta) superfamily, playing essential roles in embryonic development and tissue homeostasis.

These proteins are often studied using various techniques such as biochemistry, genetics, molecular biology, and structural biology to understand their functions, interactions, and regulation within the cell.

A frameshift mutation is a type of genetic mutation that occurs when the addition or deletion of nucleotides in a DNA sequence is not divisible by three. Since DNA is read in groups of three nucleotides (codons), which each specify an amino acid, this can shift the "reading frame," leading to the insertion or deletion of one or more amino acids in the resulting protein. This can cause a protein to be significantly different from the normal protein, often resulting in a nonfunctional protein and potentially causing disease. Frameshift mutations are typically caused by insertions or deletions of nucleotides, but they can also result from more complex genetic rearrangements.

Saccharomyces cerevisiae proteins are the proteins that are produced by the budding yeast, Saccharomyces cerevisiae. This organism is a single-celled eukaryote that has been widely used as a model organism in scientific research for many years due to its relatively simple genetic makeup and its similarity to higher eukaryotic cells.

The genome of Saccharomyces cerevisiae has been fully sequenced, and it is estimated to contain approximately 6,000 genes that encode proteins. These proteins play a wide variety of roles in the cell, including catalyzing metabolic reactions, regulating gene expression, maintaining the structure of the cell, and responding to environmental stimuli.

Many Saccharomyces cerevisiae proteins have human homologs and are involved in similar biological processes, making this organism a valuable tool for studying human disease. For example, many of the proteins involved in DNA replication, repair, and recombination in yeast have human counterparts that are associated with cancer and other diseases. By studying these proteins in yeast, researchers can gain insights into their function and regulation in humans, which may lead to new treatments for disease.

DNA, or deoxyribonucleic acid, is the genetic material present in the cells of all living organisms, including plants. In plants, DNA is located in the nucleus of a cell, as well as in chloroplasts and mitochondria. Plant DNA contains the instructions for the development, growth, and function of the plant, and is passed down from one generation to the next through the process of reproduction.

The structure of DNA is a double helix, formed by two strands of nucleotides that are linked together by hydrogen bonds. Each nucleotide contains a sugar molecule (deoxyribose), a phosphate group, and a nitrogenous base. There are four types of nitrogenous bases in DNA: adenine (A), guanine (G), cytosine (C), and thymine (T). Adenine pairs with thymine, and guanine pairs with cytosine, forming the rungs of the ladder that make up the double helix.

The genetic information in DNA is encoded in the sequence of these nitrogenous bases. Large sequences of bases form genes, which provide the instructions for the production of proteins. The process of gene expression involves transcribing the DNA sequence into a complementary RNA molecule, which is then translated into a protein.

Plant DNA is similar to animal DNA in many ways, but there are also some differences. For example, plant DNA contains a higher proportion of repetitive sequences and transposable elements, which are mobile genetic elements that can move around the genome and cause mutations. Additionally, plant cells have cell walls and chloroplasts, which are not present in animal cells, and these structures contain their own DNA.

In genetics, sequence alignment is the process of arranging two or more DNA, RNA, or protein sequences to identify regions of similarity or homology between them. This is often done using computational methods to compare the nucleotide or amino acid sequences and identify matching patterns, which can provide insight into evolutionary relationships, functional domains, or potential genetic disorders. The alignment process typically involves adjusting gaps and mismatches in the sequences to maximize the similarity between them, resulting in an aligned sequence that can be visually represented and analyzed.

Inheritance patterns refer to the way in which a particular genetic trait or disorder is passed down from one generation to the next, following the rules of Mendelian genetics. There are several different inheritance patterns, including:

1. Autosomal dominant: A single copy of the altered gene in each cell is sufficient to cause the disorder. An affected parent has a 50% chance of passing on the altered gene to each offspring.
2. Autosomal recessive: Two copies of the altered gene in each cell are necessary for the disorder to occur. Both parents must be carriers of the altered gene and have a 25% chance of passing on the altered gene to each offspring, who may then develop the disorder.
3. X-linked dominant: The altered gene is located on the X chromosome, and one copy of the altered gene in each cell is sufficient to cause the disorder. Females are more likely to be affected than males, and an affected female has a 50% chance of passing on the altered gene to each offspring.
4. X-linked recessive: The altered gene is located on the X chromosome, and two copies of the altered gene in each cell are necessary for the disorder to occur. Males are more likely to be affected than females, and an affected male will pass on the altered gene to all of his daughters (who will be carriers) but none of his sons.
5. Mitochondrial inheritance: The altered gene is located in the mitochondria, the energy-producing structures in cells. Both males and females can pass on mitochondrial genetic disorders, but only through the female line because offspring inherit their mother's mitochondria.

Understanding inheritance patterns helps medical professionals predict the likelihood of a genetic disorder occurring in families and provides information about how a disorder may be passed down through generations.

A pseudodeficiency allele may indicate a deficiency of the enzyme assay method, or it may reflect incomplete understanding of ... A pseudodeficiency allele or pseudodeficiency mutation is a mutation that alters the protein product or changes the gene's ... Because of pseudodeficiency alleles, the results of enzyme assay testing in one population cannot be generalized to other ... One possible cause of false positive results is a pseudodeficiency allele. Disease may also be present, but at a subclinical ...
Beyond this number of alleles, the selective advantage of presence of those alleles in heterozygous genotypes would be ... that there were a large enough number of alleles so that any mutation would lead to a different allele (that is the probability ... The infinite alleles model is a mathematical model for calculating genetic mutations. The Japanese geneticist Motoo Kimura and ... The effective number of alleles n maintained in a population is defined as the inverse of the homozygosity, that is n = 1 F = 4 ...
Wild type alleles are often denoted by a superscript plus sign (i.e., p+ for an allele p). A population or species of organisms ... It is now known that each of the A, B, and O alleles is actually a class of multiple alleles with different DNA sequences that ... Popular definitions of 'allele' typically refer only to different alleles within genes. For example, the ABO blood grouping is ... Look up allele in Wiktionary, the free dictionary. ALFRED: The ALlele FREquency Database (Articles with short description, ...
Beneficial alleles tend to increase in frequency, while deleterious alleles tend to decrease in frequency. Even when an allele ... For 3 alleles see Allele § Genotype frequencies) Allele frequency can always be calculated from genotype frequency, whereas the ... then the frequency p of the A-allele and the frequency q of the B-allele in the population are obtained by counting alleles. p ... Earth Human STR Allele Frequencies Database VWA 17 Allele Frequency in Human Population (Poster) Allele Frequencies in ...
Alleles that need only be present in one copy in an organism to be fatal are referred to as dominant lethal alleles. These ... Lethal alleles (also referred to as lethal or lethals) are alleles that cause the death of the organism that carries them. They ... Lethal alleles may be recessive, dominant, or conditional depending on the gene or genes involved. Lethal alleles can be ... This was the first documented example of a recessive lethal allele. A pair of identical alleles that are both present in an ...
Estimating allele age based on the allele's frequency is based on the fact that alleles in high frequency are older than ... Allele age (or mutation age) is the amount of time elapsed since an allele first appeared due to mutation. Estimating the time ... Allele age can be estimated based on (1) the frequency of the allele in a population and (2) the genetic variation that occurs ... This same study also used the allele frequency and the Kimura-Ohta model to estimate allele age. This method provided very ...
... a fixed allele is an allele that is the only variant that exists for that gene in a population. A fixed allele is homozygous ... often having certain alleles make an organism more susceptible to a disease than having other alleles; if an allele highly ... If an allele is fixed in the population, then all organisms can have only that allele for the gene in question. Suppose that ... An allele in a population being fixed necessarily entails the phenotypic traits corresponding to that allele to be identical ...
One example of a null allele is the 'O' blood type allele in the human A, B and O blood type system. The alleles for the A- ... Null alleles are difficult to identify because a heterozygous individual for one null allele and one active allele is ... The allele for O blood type, however, is a mutated version of the allele for the A-antigen, with a single base pair change due ... A null allele is a nonfunctional allele (a variant of a gene) caused by a genetic mutation. Such mutations can cause a complete ...
"Watch Kizuna no Allele". Crunchyroll. Retrieved 7 October 2023. 絆のアリル 「もう一つのユーフォリア」(テレビ東京、2023/4/3 25:30 OA)の番組情報ページ. TV Tokyo ... Kizuna no Allele (Japanese: 絆のアリル, Hepburn: Kizuna no Ariru) is a Japanese anime television series from Wit Studio and Signal. ... In November 2022, the anime project was confirmed to be a television series titled Kizuna no Allele, set to air in 2023, with a ... Mateo, Alex (30 March 2023). "Crunchyroll to Stream In Another World with My Smartphone 2, Kizuna
Samples 1 and 4 only have the normal "A" allele, while samples 3 and 5 have both the "A" and "S" alleles (and are therefore ... An allele-specific oligonucleotide (ASO) is a short piece of synthetic DNA complementary to the sequence of a variable target ... It is designed (and used) in a way that makes it specific for only one version, or allele, of the DNA being tested. The length ... Conner BJ, Reyes AA, Morin C, Itakura K, Teplitz RL, and Wallace RB "Detection of sickle cell beta S-globin allele by ...
The joint allele frequency spectrum (JAFS) is the joint distribution of allele frequencies across two or more related ... In this table, a 1 indicates that the derived allele is observed at that site, while a 0 indicates the ancestral allele was ... However, sometimes the ancestral allele cannot be determined, in which case the folded allele frequency spectrum may be ... is the distribution of the allele frequencies of a given set of loci (often SNPs) in a population or sample. Because an allele ...
... (MAF) is the frequency at which the second most common allele occurs in a given population. They play a ... Allele frequency Hernandez, Ryan D.; Uricchio, Lawrence H.; Hartman, Kevin; Ye, Chun; Dahl, Andrew; Zaitlen, Noah (September ... MAF/MinorAlleleCount: C=0.1506/754 (1000 Genomes, where number of genomes sampled = N = 2504); where C is the minor allele for ... Single nucleotide polymorphisms (SNPs) with a minor allele frequency of 0.05 (5%) or greater were targeted by the HapMap ...
If QC is to be used for mapping population non-parental alleles are discarded and alleles for which more than 90% of SNPs are ... Kompetitive allele specific PCR (KASP) is a homogenous, fluorescence-based genotyping variant of polymerase chain reaction. It ... In the first round of PCR, a KASP primer mix that contains the two allele-specific forward primers and the single reverse ... In the second round of PCR, the complementary strand to the allele-specific forward primer is generated when the common reverse ...
The Allele Frequency Net Database (abbreviated AlFreD) is a database containing the allele frequencies of immune genes and ... Allele Frequency Net Database v t e (Biological databases, Immunology, Population genetics, All stub articles, Biological ... Gonzalez-Galarza, Faviel F; Christmas Stephen; Middleton Derek; Jones Andrew R (Jan 2011). "Allele frequency net: a database ...
Allele Frequency Global Tracking (AFGT) - allows searching for allele frequency distribution at global and regional level. STR ... The Earth Human STR Allele Frequencies Database is a scientific project based on a dynamic web interface and a relational ... Population Genetics DNA profiling Short Tandem Repeat List of online databases EHSTRAFD - Earth Human STR Allele Frequencies ... the allele frequencies gradient distribution over vast geographical areas. ...
There are many human leukocyte antigen (HLA) alleles associated with conditions of or affecting the human integumentary system ...
"Protective alleles". arep.med.harvard.edu. Retrieved 25 July 2021. Harmon A (2017-02-14). "Human Gene Editing Receives Science ... The ideal gene therapy practice is that which replaces the defective gene with a normal allele at its natural location. This is ...
"Protective alleles". arep.med.harvard.edu. Retrieved 25 July 2021. (CS1 maint: bot: original URL status unknown, CS1: long ...
September 2016). "BMP2 alleles". eLife. 5. doi:10.7554/eLife.20125. PMC 5045293. PMID 27606499. Bai S, Shi X, Yang X, Cao X ( ...
"Protective alleles". arep.med.harvard.edu. Retrieved 25 July 2021. Eising, Else; Mirza-Schreiber, Nazanin; de Zeeuw, Eveline L ...
Multiple alleles refers to the situation when there are more than 2 common alleles of a particular gene. Blood groups in humans ... and multiple alleles. Incomplete dominance is the condition in which neither allele dominates the other in one heterozygote. ... The ABO blood group proteins are important in determining blood type in humans, and this is determined by different alleles of ... Thus you can tell that each allele is present in the heterozygote. Codominance refers to the allelic relationship that occurs ...
derived from IMGT/HLA Middleton D, Menchaca L, Rood H, Komerofsky R (2003). "New allele frequency database: http://www. ...
derived from IMGT/HLA Middleton, D.; Menchaca, L.; Rood, H.; Komerofsky, R. (2003). "New allele frequency database: http://www. ...
... this allele was likely represented in the first wave of immigrants. However, in areas were mixtures of these alleles are ... For A34, the alpha "A" chain are encoded by the HLA-A*34 allele group and the β-chain are encoded by B2M locus. A34 and A*34 ... Allele Query Form IMGT/HLA - European Bioinformatics Institute Middleton D, Menchaca L, Rood H, Komerofsky R (2003). "New ... but questionable whether these are perpetually maintained allele frequencies are simply recent migrants. A*3402 is more ...
derived from IMGT/HLA Middleton, D.; Menchaca, L.; Rood, H.; Komerofsky, R. (2003). "New allele frequency database: http://www. ...
For A23, the alpha, "A", chain are encoded by the HLA-A*23 allele group and the β-chain are encoded by B2M locus. This group ... Allele Query Form IMGT/HLA - European Bioinformatics Institute Middleton, D.; Menchaca, L.; Rood, H.; Komerofsky, R. (2003). " ... "Favorable and unfavorable HLA class I alleles and haplotypes in Zambians predominantly infected with clade C human ... "New allele frequency database: http://www.allelefrequencies.net". Tissue Antigens. 61 (5): 403-407. doi:10.1034/j.1399- ...
The ancestral A10 type is believed to be A*2601, which via gene conversion with other HLA-A alleles produced A*2501, A*3401, A* ... Bugawan TL, Mack SJ, Stoneking M, Saha M, Beck HP, Erlich HA (1999). "HLA class I allele distributions in six Pacific/Asian ... A34 is an excellent example, appearing to have expanded from the middle east, with linkage disequilibrium with B alleles into ... 2004). "HLA class-I and class-II allele frequencies and two-locus haplotypes in Melanesians of Vanuatu and New Caledonia" (PDF ...
... the ε2 allele is protective relative to the common ε3 allele. These gene alleles encode three apoE protein isoforms that differ ... While the ε4 allele of the APOE gene significantly increases AD risk, ...
... are the first allele frequency and genotype prevalence estimates of human genetic variants for the entire U.S. population. ... Allele. % (95% CI). Chi-square. P-value†. Genotype. % (95% CI). Chi-square. P-value†. HW. P-value‡. ... Allele. % (95% CI). Chi-square. P-value. Genotype. % (95% CI). Chi-square. P-value. ... Allele. % (95% CI). Chi-square. P-value. Genotype. % (95% CI). Chi-square. P-value. ...
2024 Allele Frequencies Website. Allele frequency net database (AFND) 2020 update: gold-standard data classification, open ... Allele Frequencies. Haplotype Frequencies. Genotype Data (download csv) Ambiguity-resolved Genotype Data (download csv) ...
No studies have looked at the effect of high-risk APOL1 alleles on donor outcomes, though few transplantation centers in the ... Screening all African Americans for high-risk APOL1 alleles may result in the exclusion of many potential donors (~13% of ... potential African American donors the relative increase in risk that is likely conferred by carrying 2 high-risk APOL1 alleles ...
HLA Database Allele Report. The list below shows all populations in AFND that contains the allele. If an allele has an entry ... Allele Frequency: Total number of copies of the allele in the population sample (Alleles / 2n) in decimal format. Important: ... Allele reported 34 time(s) and present in 1 population(s).. Population. Phenotype Frequency (%). Allele Frequency (in_decimals) ... 2024 Allele Frequencies Website. Allele frequency net database (AFND) 2020 update: gold-standard data classification, open ...
You have to enable JavaScript in your browsers settings in order to use the eReader.. Or try downloading the content offline. DOWNLOAD ...
The NCBI Allele Frequency Aggregator (ALFA) project makes frequency data from dbGaP data studies, previously under authorized ... ALFA computes allele frequencies for 12 major populations, including European, Hispanic, African, Asian and other diverse ... NCBI ALFA: Open-Access to dbGaP Aggregated Allele Frequency for Variant Interpretation. NCBI ALFA: Open-Access to dbGaP ... ALFA data is integrated with dbSNP and includes 720 million Reference SNP (rs) and existing allele frequencies reported for ...
Again, I think thats why we need sort of a funnel mechanism where were broadly surveying many of the risk genes and alleles ... Is there anything we can do now to really start the process of interrogating specific genes or alleles and testing them? What ... all these phenotypes are circuit based and using approaches to directly target the circuit rather than the gene or the allele. ... that we are really getting tractable genes and alleles that are risk genes with high effect sizes and some causal, especially ...
Mouse Models Containing Human Alleles: Novel Tools to Study Brain Function (R21/R33) PAR-08-158. NIMH ... Title:Mouse Models Containing Human Alleles: Novel Tools to Study Brain Function (R21/R33). Announcement Type This FOA is a ... Expressing specific human alleles of interest in mice may help elucidate gene/protein regulation and function and can provide ... Although currently unclear, some of these may be specific disease alleles with polymorphisms present either in coding regions ...
... Defective Alleles in Liver Enzymes Linked to Poor Drug ... Identification and functional characterization of new potentially defective alleles of human CYP2C19. Pharmacogenetics. 12(9): ... in the Human Metabolism Group announced the identification and functional characterization of potentially defective alleles in ...
Nationwide Monitoring for Plasmodium falciparum Drug-Resistance Alleles to Chloroquine, Sulfadoxine, and Pyrimethamine, Haiti, ... Nationwide Monitoring for Plasmodium falciparum Drug-Resistance Alleles to Chloroquine, Sulfadoxine, and Pyrimethamine, Haiti, ...
More recently, severe and even fatal drug hypersensitivity reactions linked to particular HLA alleles have been discovered. The ... HLA alleles and drug hypersensitivity reactions T Profaizer et al. Int J Immunogenet. 2012 Apr. ... This review will outline and discuss these three drugs and their associated HLA alleles as well as examine the pathogenesis of ... The associations between idiosyncratic adverse drug reactions and HLA alleles and their underlying mechanism]. Wang Q, Mei H, ...
Additional gonococcal-like alleles were acquired as the clade diversified. Notably, one isolate contained a sequence associated ... Ongoing acquisition of N. gonorrhoeae alleles by the U.S. NmNG urethritis clade may facilitate the expansion of its ecological ... The ancestor contained N. gonorrhoeae-like alleles in three regions of its genome, two of which may facilitate nitrite- ... gonorrhoeae alleles Personal Author(s) : Retchless, Adam C.;Kretz, Cécilia B.;Chang, How-Yi;Bazan, Jose A.;Abrams, A. Jeanine; ...
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This allele is not present in the registry. To get a canonical identifier, please click on the "Get identifier" below.. ...
Allele. List of germplasm that has been detected to have allele 1 using marker S-locus ...
Alleles Alleles of this type are documented at Mouse Genome Informatics (MGI) ...
Index of /releases/FB2023_03/precomputed_files/alleles. Name. Last modified. Size. Description. ...
Alleles Curated mutant alleles for the specified gene, listed alphabetically. Click on the allele name to open the allele page ... Click "SGD search" to view all alleles in search results. Click "YeastMine" to view all alleles in YeastMine. ... View all ECM29 alleles in SGD search , YeastMine Gene Ontology Details Gene Ontology GO Annotations consist of four mandatory ... allele information and additional details are provided. Click "Phenotype Details" to view all phenotype annotations and ...
Kizuna no Allele Season 2 subtitle indonesia Admin Hidoridenime , Kamis, Desember 21, 2023 , K Kizuna no Allele Season 2 ... Kizuna no Allele Season 2 Kizuna no Allele Season 2 subtitle indonesia ... Sinopsis: Musim kedua Kizuna no Allele. link download Kizuna no Allele Season 2 subtitle indonesia ...
Distribution of derived alleles by functional class. Derived alleles, n (%). Polymorphic positions (SNPs). Homozygous positions ... See Table S19 for the actual allele counts and Fig. S10 for the frequency spectra of nonsynonymous derived alleles assessed by ... S5 and S6). Reference allele frequencies in El Sidrón and Vindija exomes are within the range of reference allele frequencies ... Furthermore, when counting putatively deleterious alleles per individual, we used only derived alleles that did not match the ...
FGFR4 Arg388 allele is associated with resistance to adjuvant therapy in primary breast cancer. J Clin Oncol 2006; 24:3747-3755 ... FGFR4 polymorphic alleles modulate mitochondrial respiration: A novel target for somatostatin analog action in pituitary tumors ... Recently we reported that the FGFR4-R388 allele modulates GH levels and is associated with larger pituitary tumor size in ... The FGFR4-R388 polymorphic allele promotes resistance to octreotide. To compare the impact of the different FGFR4 isoforms on ...
Gene Alleles Show all alleles for a specific Drosophila gene. Show all available information, eg mutagen, allele class and ...
Allele Mining for Genomic Designing of Fruit Crops Chittaranjan Kole Flere utgaver E-bok 640,- E-bok 640,- ... Allele Mining for Genomic Designing of Vegetable Crops Chittaranjan Kole E-bok ...
No multiple adenoma case had an outlying number of CRC SNP risk alleles, but multiple adenoma patients did have a significantly ... In conclusion, common colorectal tumour risk alleles contribute to the development of multiple adenomas in patients without ... higher number of risk alleles than population controls (P=5.7 × 10(-7)). The association was stronger in those with ≥10 ... No multiple adenoma case had an outlying number of CRC SNP risk alleles, but multiple adenoma patients did have a significantly ...
Jones, MA and Hu, W and Litthauer, S and Lagarias, JC and Harmer, SL (2015) A Constitutively Active Allele of Phytochrome B ... Jones, MA and Hu, W and Litthauer, S and Lagarias, JC and Harmer, SL (2015) A Constitutively Active Allele of Phytochrome B ... Jones, MA and Hu, W and Litthauer, S and Lagarias, JC and Harmer, SL (2015) A Constitutively Active Allele of Phytochrome B ... A Constitutively Active Allele of Phytochrome B Maintains Circadian Robustness in the Absence of Light ...
A Study to Evaluate AZD2693 in Participants Who Are Carriers of the PNPLA3 148M Risk Allele With Non-cirrhotic Non-alcoholic ... A Study to Evaluate AZD2693 in Participants Who Are Carriers of the PNPLA3 148M Risk Allele With Non-cirrhotic Non-alcoholic ... Participants who are carriers for the PNPLA3 rs738409 148M risk allele.. * Participants with histological evidence of NASH ... 2-point improvement in NASH in participants who are carriers of the PNPLA3 risk allele ...
Alleles. 1. 2024. 6939. 0.030. Why? Cell Line, Tumor. 1. 2019. 16624. 0.030. Why? ...
Alleles. 1. 2018. 6931. 0.020. Why? Schizophrenic Psychology. 1. 2014. 1677. 0.020. Why? ...
  • Several parameters, such as allele frequencies, Hardy-Weinberg equilibrium, power of exclusion, power of discrimination, pairwise comparison, were calculated and correction test was used to confirm significant differences found in the comparative analysis. (tubitak.gov.tr)
  • 0.99, while only 206 allele frequencies (69%) were correctly estimated in the pre-PCR pooling, the correlation being 0.89. (elsevierpure.com)
  • In addition, databases that aggregate allele frequencies, such as gnomAD are also biased toward European populations and contain very little information from individuals of African or other ancestries. (cdc.gov)
  • The lack of diverse ethnic representation in these data has created a gap in knowledge about the alleles present in non-White populations and their relative frequencies. (cdc.gov)
  • This could cause health inequities because the results of PGx tests that were designed based on allele frequencies of Europeans are being applied to patients of other ethnicities, causing physicians to prescribe drugs and doses that are ineffective or may cause adverse reactions in non-White patients. (cdc.gov)
  • To obtain a more complete picture of the PGx alleles present in a diverse US population, approximately 5,000 DNA samples from the population-based NHANES will be tested to determine the PGx allele frequencies of 970 unique haplotypes in 150 pharmacogenes. (cdc.gov)
  • Allele frequencies will also be correlated with prescription drug use among the different ethnic groups to study whether drugs prescribed for each are appropriate given the PGx allele frequency determined for the population and how the drugs prescribed could be modified if more comprehensive PGx testing were available. (cdc.gov)
  • Creation of the comprehensive PGx data set proposed in this project will, for the first time, help to establish the allele frequencies in 150 pharmacogenes across ethnicities in the US population. (cdc.gov)
  • H63D, S65C and C282Y allele frequencies were 30.5%, 13.4% and 7.3% respectively in -thalassaemia carriers and 10.0%, 2.5% and 0.0% respectively in the control group. (who.int)
  • Estimated average heterozygosity from allele frequencies of this RefSNP. (lu.se)
  • In other words, if there are 3 alleles, with frequencies of 0.50, 0.49, and 0.01, the MAF will be reported as 0.49. (lu.se)
  • For some genetic diseases, especially those that have low penetrance or are easily treatable, carrier screening may be of questionable value when pseudodeficiency alleles are present at high frequency. (wikipedia.org)
  • Methods: We examined the approach of sequencing pooled mtDNA of multiple individuals for estimating allele frequency using the Illumina genome analyzer (GA) II sequencing system. (elsevierpure.com)
  • OCD patients did not show significant differences in genotype distribution and allele frequency for polymorphisms investigated relative to controls. (qxmd.com)
  • However, when the sample was stratified by gender, there was a trend to a significant predominance of the DRD2 A2A2 genotype (p=0.049), and a higher frequency of the DRD2 A2 allele (p=0.020) and low-activity COMT allele (p=0.035) in male OCD patients compared to male controls. (qxmd.com)
  • Collectively, our results imply that AgA and AgD are T-cell antigens with a high HLA binding frequency as well as population coverage for HLA alleles. (cdc.gov)
  • The PGx alleles will be correlated with sample ethnicity to determine the allele frequency of each pharmacogene in the various population groups. (cdc.gov)
  • dbSNP is reporting the minor allele frequency for each rs included in a default global population. (lu.se)
  • Upstream sequences were also identified for a set of previously uncharacterized germline gene alleles. (lu.se)
  • Most HLA-B gene alleles are rare, while others do not affect protein function or change the structure of the protein. (medlineplus.gov)
  • Since this is being provided to distinguish common polymorphism from rare variants, the MAF is actually the second most frequent allele value. (lu.se)
  • States revealed the emerging mosaic penA 60 allele, first identi- for testing and treatment and received ceftriaxone (250 mg) fied in Japan in 2016 ( 1 ), which confers reduced susceptibility intramuscularly and azithromycin (1 g) orally. (cdc.gov)
  • INTRODUCTION: More than 70 common alleles are known to be involved in breast cancer (BC) susceptibility, and several exhibit significant heterogeneity in their associations with different BC subtypes. (lu.se)
  • Although there are differences in the association patterns between BRCA1 and BRCA2 mutation carriers and the general population for several loci, no study has comprehensively evaluated the associations of all known BC susceptibility alleles with risk of BC subtypes in BRCA1 and BRCA2 carriers. (lu.se)
  • CONCLUSIONS: Differences in associations of common BC susceptibility alleles between BRCA1 and BRCA2 carriers and the general population are explained to a large extent by differences in the prevalence of ER-positive and ER-negative tumors. (lu.se)
  • Finally, based on the outcomes of the analysis, we define a set of testable hypotheses with respect to the placement of particular alleles in complex IGHV locus haplotypes, and discuss the evolutionary relatedness of particular heavy chain variable genes based on sequences of their upstream regions. (lu.se)
  • Other genetic determinants include the apolipoprotein (apo) E (epsilon) alleles. (msdmanuals.com)
  • Assertions of clinical significance for alleles of human sequence variations are reported as provided by the submitter and not interpreted by NCBI. (lu.se)
  • Allele distribution data for 16 short tandem repeat loci in Bolu" by AYŞİM TUĞ, ZERRİN ERKOL et al. (tubitak.gov.tr)
  • Inference of ancestral alleles in the pig reference genome. (bvsalud.org)
  • Notre étude a démontré que les mutations du gène HFE sont fréquentes en Égypte chez les porteurs d'une -thalassémie par rapport aux sujets témoins. (who.int)
  • Because of pseudodeficiency alleles, the results of enzyme assay testing in one population cannot be generalized to other populations. (wikipedia.org)
  • This will facilitate development and validation of PGx tests capable of detecting important PGx alleles in African American, Asian, Hispanic, and White populations. (cdc.gov)
  • Curated mutant alleles for the specified gene, listed alphabetically. (yeastgenome.org)
  • for example, more than 60 very similar alleles are subtypes of HLA-B27 . (medlineplus.gov)
  • A pseudodeficiency allele or pseudodeficiency mutation is a mutation that alters the protein product or changes the gene's expression, but without causing disease. (wikipedia.org)
  • Additional HLA-B alleles play a smaller role in disease risk: the HLA-B47 and HLA-B51 alleles can contribute to increased risk, whereas the HLA-B7 and HLA-B57 alleles might provide some small amount of protection against developing the condition. (medlineplus.gov)
  • Risk of Alzheimer disease is substantially increased in people with two epsilon-4 alleles and may be decreased in those who have the epsilon-2 allele. (msdmanuals.com)
  • For people with two epsilon-4 alleles, risk of developing Alzheimer disease by age 75 is about 10 to 30 times that for people without the allele. (msdmanuals.com)
  • For example, in the lysosomal storage diseases, patients with a pseudodeficiency allele show greatly reduced enzyme activity, yet they remain clinically healthy. (wikipedia.org)
  • The availability of PGx tests that more accurately detect important PGx alleles will greatly improve health equity and patient care and facilitate a more equitable implementation of genomic findings. (cdc.gov)
  • Immuno-informatic analysis predicted that the identified T-cell antigens (AgA and AgD) bind more number of class I and class II HLA alleles as compared with the reference immuno-dominant antigens ESAT-6 and CFP-10 from the tuberculous mycobacterial species M. tuberculosis. (cdc.gov)
  • All allele(s) observed at this position in the reference. (lu.se)
  • RESULTS: The estimated BC hazard ratios (HRs) for the 74 known BC alleles in BRCA1 carriers exhibited moderate correlations with the corresponding odds ratios from the general population. (lu.se)
  • Enzyme assay testing was especially effective among Ashkenazi Jews because fewer pseudodeficiency alleles are found in this population, as compared with the general population. (wikipedia.org)
  • independent molecular testing for the mosaic penA 60 allele part of the project, the Sexual Health Clinic at SNHD collects of the remnant NAATs ( 6 ) identified no additional isolates urethral samples for gonococcal culturing from the first 25 men with the mosaic penA 60 allele. (cdc.gov)
  • Click "SGD search" to view all alleles in search results. (yeastgenome.org)
  • If there is a published authoritative guideline about the pathogenicity of any allele, that is included in the report. (lu.se)
  • While the ε4 allele of the APOE gene significantly increases AD risk, the ε2 allele is protective relative to the common ε3 allele. (nih.gov)
  • These gene alleles encode three apoE protein isoforms that differ at two amino acid positions. (nih.gov)
  • Phenotype Frequency: Percentage of individuals who have the allele or gene (Individuals / n). (allelefrequencies.net)
  • Curated mutant alleles for the specified gene, listed alphabetically. (yeastgenome.org)
  • Show all alleles for a specific Drosophila gene. (flymine.org)
  • In that gene, the DNA occurs in two possible forms (or alleles). (collie-online.com)
  • Most HLA-B gene alleles are rare, while others do not affect protein function or change the structure of the protein. (medlineplus.gov)
  • Hundreds of versions (alleles) of the HLA-B gene are known, each of which is given a particular number (such as HLA-B27 ). (medlineplus.gov)
  • In this study, we identified and characterized two variant microsatellite alleles in the mitochondrial NAD6 gene of S. frugiperda retrieved from the National Center for Biotechnology Center GenBank. (bioone.org)
  • Exactly how the AD risk variant near the clusterin gene affects the clusterin protein, and how the allele contributes to risk, remains a puzzle. (alzforum.org)
  • These models typically consider a modifier allele that changes the mutation rate at other fitness-affecting loci (e.g. immunity loci) and then identify the conditions under which such a modifier spreads. (royalsocietypublishing.org)
  • However, we also find that maternal transmission can eliminate coevolutionary fluctuations in allele frequency that previous work has found are essential for the evolution of elevated mutation rates [ 3 ]. (royalsocietypublishing.org)
  • Identification of a novel HLA-DPB1 allele (DPB1*1902) by haplotype-specific extraction and nucleotide sequencing. (cdc.gov)
  • Allele Frequencies shown in green were calculated from Phenotype Frequencies assuming Hardy-Weinberg proportions. (allelefrequencies.net)
  • Show all available information, eg mutagen, allele class and phenotype linked to each allele. (flymine.org)
  • Common colorectal cancer risk alleles contribute to the multiple colorectal adenoma phenotype, but do not influence colonic polyposis in FAP. (ox.ac.uk)
  • Comparisons with present-day humans from Africa, Europe, and Asia reveal that genetic diversity among Neandertals was remarkably low, and that they carried a higher proportion of amino acid-changing (nonsynonymous) alleles inferred to alter protein structure or function than present-day humans. (pnas.org)
  • No studies have looked at the effect of high-risk APOL1 alleles on donor outcomes, though few transplantation centers in the United States offer screening for APOL1 among African American donors. (medscape.com)
  • The list below shows all populations in AFND that contains the allele. (allelefrequencies.net)
  • ALFA computes allele frequencies for 12 major populations, including European, Hispanic, African, Asian and other diverse population ancestries, to access the prevalence of common variants and rare disease mutations in humans. (nih.gov)
  • 2024 Allele Frequencies Website. (allelefrequencies.net)
  • ALFA data is integrated with dbSNP and includes 720 million Reference SNP (rs) and existing allele frequencies reported for over 606 million rs from various projects, including 1000Genomes, ExAc, GnomAD, TopMed and many others for cross-studies comparisons. (nih.gov)
  • Screening all African Americans for high-risk APOL1 alleles may result in the exclusion of many potential donors (~13% of African Americans). (medscape.com)
  • Nephrologists should be prepared to discuss with potential African American donors the relative increase in risk that is likely conferred by carrying 2 high-risk APOL1 alleles and how additional factors such as environmental exposures (eg, viral infections) and/or other genetic susceptibilities may be required for developing kidney disease. (medscape.com)
  • Human hypervariable sequences in risk assessment: rare Ha-ras alleles in cancer patients. (nih.gov)
  • In conclusion, common colorectal tumour risk alleles contribute to the development of multiple adenomas in patients without pathogenic germline APC or MUTYH variants. (ox.ac.uk)
  • Additional HLA-B alleles play a smaller role in disease risk: the HLA-B47 and HLA-B51 alleles can contribute to increased risk, whereas the HLA-B7 and HLA-B57 alleles might provide some small amount of protection against developing the condition. (medlineplus.gov)
  • NIEHS researchers in the Human Metabolism Group announced the identification and functional characterization of potentially defective alleles in human liver enzymes that are responsible for metabolizing therapeutic drugs, including anti-clotting medications and antidepressants. (nih.gov)
  • 2002. Identification and functional characterization of new potentially defective alleles of human CYP2C19. (nih.gov)
  • Click "SGD search" to view all alleles in search results. (yeastgenome.org)
  • To date, the following drugs have been identified as causing significant drug hypersensitivity reactions in patients who have the following HLA alleles: abacavir and HLA-B*57:01, carbamazepine and HLA-B*15:02/A*31:01 and finally allopurinol and HLA-B*58:01. (nih.gov)
  • We genotyped KIRs and HLA class I alleles using DNA from uninfected controls, EVD survivors, and persons who died of EVD. (cdc.gov)