Heterozygote. Medical search

An individual having different alleles at one or more loci regarding a specific character.

Identification of genetic carriers for a given trait.

An individual in which both alleles at a given locus are identical.

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.

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.

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 outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.

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.

The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.

A group of hereditary hemolytic anemias in which there is decreased synthesis of one or more hemoglobin polypeptide chains. There are several genetic types with clinical pictures ranging from barely detectable hematologic abnormality to severe and fatal anemia.

Genes that influence the PHENOTYPE only in the homozygous state.

An inherited condition due to a deficiency of either LIPOPROTEIN LIPASE or APOLIPOPROTEIN C-II (a lipase-activating protein). The lack of lipase activities results in inability to remove CHYLOMICRONS and TRIGLYCERIDES from the blood which has a creamy top layer after standing.

An adult hemoglobin component normally present in hemolysates from human erythrocytes in concentrations of about 3%. The hemoglobin is composed of two alpha chains and two delta chains. The percentage of HbA2 varies in some hematologic disorders, but is about double in beta-thalassemia.

Genotypic differences observed among individuals in a population.

Genes that influence the PHENOTYPE both in the homozygous and the heterozygous state.

Biochemical identification of mutational changes in a nucleotide sequence.

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.

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.

The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.

Hemoglobins characterized by structural alterations within the molecule. The alteration can be either absence, addition or substitution of one or more amino acids in the globin part of the molecule at selected positions in the polypeptide chains.

A disorder of iron metabolism characterized by a triad of HEMOSIDEROSIS; LIVER CIRRHOSIS; and DIABETES MELLITUS. It is caused by massive iron deposits in parenchymal cells that may develop after a prolonged increase of iron absorption. (Jablonski's Dictionary of Syndromes & Eponymic Diseases, 2d ed)

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.

An autosomal recessive inherited disorder characterized by choreoathetosis beginning in childhood, progressive CEREBELLAR ATAXIA; TELANGIECTASIS of CONJUNCTIVA and SKIN; DYSARTHRIA; B- and T-cell immunodeficiency, and RADIOSENSITIVITY to IONIZING RADIATION. Affected individuals are prone to recurrent sinobronchopulmonary infections, lymphoreticular neoplasms, and other malignancies. Serum ALPHA-FETOPROTEINS are usually elevated. (Menkes, Textbook of Child Neurology, 5th ed, p688) The gene for this disorder (ATM) encodes a cell cycle checkpoint protein kinase and has been mapped to chromosome 11 (11q22-q23).

A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.

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.

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.

A group of familial disorders characterized by elevated circulating cholesterol contained in either LOW-DENSITY LIPOPROTEINS alone or also in VERY-LOW-DENSITY LIPOPROTEINS (pre-beta lipoproteins).

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)

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 inherited disorder due to defective reabsorption of CYSTINE and other BASIC AMINO ACIDS by the PROXIMAL RENAL TUBULES. This form of aminoaciduria is characterized by the abnormally high urinary levels of cystine; LYSINE; ARGININE; and ORNITHINE. Mutations involve the amino acid transport protein gene SLC3A1.

Conditions with abnormally low levels of BETA-LIPOPROTEINS (low density lipoproteins or LDL) in the blood. It is defined as LDL values equal to or less than the 5th percentile for the population. They include the autosomal dominant form involving mutation of the APOLIPOPROTEINS B gene, and the autosomal recessive form involving mutation of the microsomal triglyceride transfer protein. All are characterized by low LDL and dietary fat malabsorption.

An autosomal recessive neurodegenerative disorder characterized by the onset in infancy of an exaggerated startle response, followed by paralysis, dementia, and blindness. It is caused by mutation in the alpha subunit of the HEXOSAMINIDASE A resulting in lipid-laden ganglion cells. It is also known as the B variant (with increased HEXOSAMINIDASE B but absence of hexosaminidase A) and is strongly associated with Ashkenazic Jewish ancestry.

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.

An abnormal hemoglobin that results from the substitution of lysine for glutamic acid at position 26 of the beta chain. It is most frequently observed in southeast Asian populations.

An ethnic group with historical ties to the land of ISRAEL and the religion of JUDAISM.

An enzyme catalyzing the formation of AMP from adenine and phosphoribosylpyrophosphate. It can act as a salvage enzyme for recycling of adenine into nucleic acids. EC 2.4.2.7.

The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.

Mice bearing mutant genes which are phenotypically expressed in the animals.

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 major component of hemoglobin in the fetus. This HEMOGLOBIN has two alpha and two gamma polypeptide subunits in comparison to normal adult hemoglobin, which has two alpha and two beta polypeptide subunits. Fetal hemoglobin concentrations can be elevated (usually above 0.5%) in children and adults affected by LEUKEMIA and several types of ANEMIA.

A disorder characterized by reduced synthesis of the alpha chains of hemoglobin. The severity of this condition can vary from mild anemia to death, depending on the number of genes deleted.

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.

A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.

A group of inherited disorders characterized by structural alterations within the hemoglobin molecule.

Any method used for determining the location of and relative distances between genes on a chromosome.

The mating of plants or non-human animals which are closely related genetically.

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.

Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.

An autosomal recessive neurodegenerative disorder characterized by an accumulation of G(M2) GANGLIOSIDE in neurons and other tissues. It is caused by mutation in the common beta subunit of HEXOSAMINIDASE A and HEXOSAMINIDASE B. Thus this disease is also known as the O variant since both hexosaminidase A and B are missing. Clinically, it is indistinguishable from TAY-SACHS DISEASE.

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.

A disorder characterized by reduced synthesis of the beta chains of hemoglobin. There is retardation of hemoglobin A synthesis in the heterozygous form (thalassemia minor), which is asymptomatic, while in the homozygous form (thalassemia major, Cooley's anemia, Mediterranean anemia, erythroblastic anemia), which can result in severe complications and even death, hemoglobin A synthesis is absent.

A disease-producing enzyme deficiency subject to many variants, some of which cause a deficiency of GLUCOSE-6-PHOSPHATE DEHYDROGENASE activity in erythrocytes, leading to hemolytic anemia.

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).

A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.

Disorders affecting amino acid metabolism. The majority of these disorders are inherited and present in the neonatal period with metabolic disturbances (e.g., ACIDOSIS) and neurologic manifestations. They are present at birth, although they may not become symptomatic until later in life.

A group of autosomal recessive disorders marked by a deficiency of the hepatic enzyme PHENYLALANINE HYDROXYLASE or less frequently by reduced activity of DIHYDROPTERIDINE REDUCTASE (i.e., atypical phenylketonuria). Classical phenylketonuria is caused by a severe deficiency of phenylalanine hydroxylase and presents in infancy with developmental delay; SEIZURES; skin HYPOPIGMENTATION; ECZEMA; and demyelination in the central nervous system. (From Adams et al., Principles of Neurology, 6th ed, p952).

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 superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.

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.

Differential and non-random reproduction of different genotypes, operating to alter the gene frequencies within a population.

Errors in the metabolism of LIPIDS resulting from inborn genetic MUTATIONS that are heritable.

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.

Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.

An amino acid-specifying codon that has been converted to a stop codon (CODON, TERMINATOR) by mutation. Its occurance is abnormal causing premature termination of protein translation and results in production of truncated and non-functional proteins. A nonsense mutation is one that converts an amino acid-specific codon to a stop codon.

An X-linked inherited metabolic disease caused by a deficiency of lysosomal ALPHA-GALACTOSIDASE A. It is characterized by intralysosomal accumulation of globotriaosylceramide and other GLYCOSPHINGOLIPIDS in blood vessels throughout the body leading to multi-system complications including renal, cardiac, cerebrovascular, and skin disorders.

Conditions with abnormally low levels of LIPOPROTEINS in the blood. This may involve any of the lipoprotein subclasses, including ALPHA-LIPOPROTEINS (high-density lipoproteins); BETA-LIPOPROTEINS (low-density lipoproteins); and PREBETA-LIPOPROTEINS (very-low-density lipoproteins).

The magnitude of INBREEDING in humans.

The adaptive superiority of the heterozygous GENOTYPE with respect to one or more characters in comparison with the corresponding HOMOZYGOTE.

A mammalian beta-hexosaminidase isoform that is a heteromeric protein comprized of both hexosaminidase alpha and hexosaminidase beta subunits. Deficiency of hexosaminidase A due to mutations in the gene encoding the hexosaminidase alpha subunit is a case of TAY-SACHS DISEASE. Deficiency of hexosaminidase A and HEXOSAMINIDASE B due to mutations in the gene encoding the hexosaminidase beta subunit is a case of SANDHOFF DISEASE.

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.

Autosomal recessive inborn error of methionine metabolism usually caused by a deficiency of CYSTATHIONINE BETA-SYNTHASE and associated with elevations of homocysteine in plasma and urine. Clinical features include a tall slender habitus, SCOLIOSIS, arachnodactyly, MUSCLE WEAKNESS, genu varus, thin blond hair, malar flush, lens dislocations, an increased incidence of MENTAL RETARDATION, and a tendency to develop fibrosis of arteries, frequently complicated by CEREBROVASCULAR ACCIDENTS and MYOCARDIAL INFARCTION. (From Adams et al., Principles of Neurology, 6th ed, p979)

Conditions characterized by abnormal lipid deposition due to disturbance in lipid metabolism, such as hereditary diseases involving lysosomal enzymes required for lipid breakdown. They are classified either by the enzyme defect or by the type of lipid involved.

An autosomal recessively inherited disorder caused by mutation of LECITHIN CHOLESTEROL ACYLTRANSFERASE that facilitates the esterification of lipoprotein cholesterol and subsequent removal from peripheral tissues to the liver. This defect results in low HDL-cholesterol level in blood and accumulation of free cholesterol in tissue leading to a triad of CORNEAL OPACITY, hemolytic anemia (ANEMIA, HEMOLYTIC), and PROTEINURIA.

An autosomal recessive genetic disease of the EXOCRINE GLANDS. It is caused by mutations in the gene encoding the CYSTIC FIBROSIS TRANSMEMBRANE CONDUCTANCE REGULATOR expressed in several organs including the LUNG, the PANCREAS, the BILIARY SYSTEM, and the SWEAT GLANDS. Cystic fibrosis is characterized by epithelial secretory dysfunction associated with ductal obstruction resulting in AIRWAY OBSTRUCTION; chronic RESPIRATORY INFECTIONS; PANCREATIC INSUFFICIENCY; maldigestion; salt depletion; and HEAT PROSTRATION.

Major structural proteins of triacylglycerol-rich LIPOPROTEINS. There are two forms, apolipoprotein B-100 and apolipoprotein B-48, both derived from a single gene. ApoB-100 expressed in the liver is found in low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). ApoB-48 expressed in the intestine is found in CHYLOMICRONS. They are important in the biosynthesis, transport, and metabolism of triacylglycerol-rich lipoproteins. Plasma Apo-B levels are high in atherosclerotic patients but non-detectable in ABETALIPOPROTEINEMIA.

The reciprocal exchange of segments at corresponding positions along pairs of homologous CHROMOSOMES by symmetrical breakage and crosswise rejoining forming cross-over sites (HOLLIDAY JUNCTIONS) that are resolved during CHROMOSOME SEGREGATION. Crossing-over typically occurs during MEIOSIS but it may also occur in the absence of meiosis, for example, with bacterial chromosomes, organelle chromosomes, or somatic cell nuclear chromosomes.

Electrophoresis in which a starch gel (a mixture of amylose and amylopectin) is used as the diffusion medium.

An inherited disorder transmitted as a sex-linked trait and caused by a deficiency of an enzyme of purine metabolism; HYPOXANTHINE PHOSPHORIBOSYLTRANSFERASE. Affected individuals are normal in the first year of life and then develop psychomotor retardation, extrapyramidal movement disorders, progressive spasticity, and seizures. Self-destructive behaviors such as biting of fingers and lips are seen frequently. Intellectual impairment may also occur but is typically not severe. Elevation of uric acid in the serum leads to the development of renal calculi and gouty arthritis. (Menkes, Textbook of Child Neurology, 5th ed, pp127)

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.

An enzyme of the hydrolase class that catalyzes the reaction of triacylglycerol and water to yield diacylglycerol and a fatty acid anion. The enzyme hydrolyzes triacylglycerols in chylomicrons, very-low-density lipoproteins, low-density lipoproteins, and diacylglycerols. It occurs on capillary endothelial surfaces, especially in mammary, muscle, and adipose tissue. Genetic deficiency of the enzyme causes familial hyperlipoproteinemia Type I. (Dorland, 27th ed) EC 3.1.1.34.

A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.

A 513-kDa protein synthesized in the LIVER. It serves as the major structural protein of low-density lipoproteins (LIPOPROTEINS, LDL; LIPOPROTEINS, VLDL). It is the ligand for the LDL receptor (RECEPTORS, LDL) that promotes cellular binding and internalization of LDL particles.

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.

A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.

The chromosomal constitution of cells, in which each type of CHROMOSOME is represented once. Symbol: N.

Deficiency of the protease inhibitor ALPHA 1-ANTITRYPSIN that manifests primarily as PULMONARY EMPHYSEMA and LIVER CIRRHOSIS.

General term for a number of inherited defects of amino acid metabolism in which there is a deficiency or absence of pigment in the eyes, skin, or hair.

An aberration in which a chromosomal segment is deleted and reinserted in the same place but turned 180 degrees from its original orientation, so that the gene sequence for the segment is reversed with respect to that of the rest of the chromosome.

An abnormal hemoglobin resulting from the substitution of valine for glutamic acid at position 6 of the beta chain of the globin moiety. The heterozygous state results in sickle cell trait, the homozygous in sickle cell anemia.

Deletion of sequences of nucleic acids from the genetic material of an individual.

A hexosaminidase specific for non-reducing N-acetyl-D-hexosamine residues in N-acetyl-beta-D-hexosaminides. It acts on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES. Two specific mammalian isoenzymes of beta-N-acetylhexoaminidase are referred to as HEXOSAMINIDASE A and HEXOSAMINIDASE B. Deficiency of the type A isoenzyme causes TAY-SACHS DISEASE, while deficiency of both A and B isozymes causes SANDHOFF DISEASE. The enzyme has also been used as a tumor marker to distinguish between malignant and benign disease.

Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.

Conditions with abnormally elevated levels of LIPOPROTEINS in the blood. They may be inherited, acquired, primary, or secondary. Hyperlipoproteinemias are classified according to the pattern of lipoproteins on electrophoresis or ultracentrifugation.

A purine that is an isomer of ADENINE (6-aminopurine).

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.

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.

Individuals whose ancestral origins are in the southeastern and eastern areas of the Asian continent.

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.

Heat- and storage-labile plasma glycoprotein which accelerates the conversion of prothrombin to thrombin in blood coagulation. Factor V accomplishes this by forming a complex with factor Xa, phospholipid, and calcium (prothrombinase complex). Deficiency of factor V leads to Owren's disease.

The naturally occurring or experimentally induced replacement of one or more AMINO ACIDS in a protein with another. If a functionally equivalent amino acid is substituted, the protein may retain wild-type activity. Substitution may also diminish, enhance, or eliminate protein function. Experimentally induced substitution is often used to study enzyme activities and binding site properties.

Color of hair or fur.

An individual having only one allele at a given locus because of the loss of the other allele through a mutation (e.g., CHROMOSOME DELETION).

In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)

The chromosomal constitution of cells, in which each type of CHROMOSOME is represented twice. Symbol: 2N or 2X.

The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species.

A condition marked by the development of widespread xanthomas, yellow tumor-like structures filled with lipid deposits. Xanthomas can be found in a variety of tissues including the SKIN; TENDONS; joints of KNEES and ELBOWS. Xanthomatosis is associated with disturbance of LIPID METABOLISM and formation of FOAM CELLS.

A phenomenon that is observed when a small subgroup of a larger POPULATION establishes itself as a separate and isolated entity. The subgroup's GENE POOL carries only a fraction of the genetic diversity of the parental population resulting in an increased frequency of certain diseases in the subgroup, especially those diseases known to be autosomal recessive.

A group of HEREDITARY AUTOINFLAMMATION DISEASES, characterized by recurrent fever, abdominal pain, headache, rash, PLEURISY; and ARTHRITIS. ORCHITIS; benign MENINGITIS; and AMYLOIDOSIS may also occur. Homozygous or compound heterozygous mutations in marenostrin gene result in autosomal recessive transmission; simple heterozygous, autosomal dominant form of the disease.

A filament-like structure consisting of a shaft which projects to the surface of the SKIN from a root which is softer than the shaft and lodges in the cavity of a HAIR FOLLICLE. It is found on most surfaces of the body.

An excessive accumulation of iron in the body due to a greater than normal absorption of iron from the gastrointestinal tract or from parenteral injection. This may arise from idiopathic hemochromatosis, excessive iron intake, chronic alcoholism, certain types of refractory anemia, or transfusional hemosiderosis. (From Churchill's Illustrated Medical Dictionary, 1989)

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.

A species of fruit fly much used in genetics because of the large size of its chromosomes.

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.

A genetic or pathological condition that is characterized by short stature and undersize. Abnormal skeletal growth usually results in an adult who is significantly below the average height.

Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.

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.

An autosomal recessively inherited disorder caused by mutation of ATP-BINDING CASSETTE TRANSPORTERS involved in cellular cholesterol removal (reverse-cholesterol transport). It is characterized by near absence of ALPHA-LIPOPROTEINS (high-density lipoproteins) in blood. The massive tissue deposition of cholesterol esters results in HEPATOMEGALY; SPLENOMEGALY; RETINITIS PIGMENTOSA; large orange tonsils; and often sensory POLYNEUROPATHY. The disorder was first found among inhabitants of Tangier Island in the Chesapeake Bay, MD.

The homologous chromosomes that are dissimilar in the heterogametic sex. There are the X CHROMOSOME, the Y CHROMOSOME, and the W, Z chromosomes (in animals in which the female is the heterogametic sex (the silkworm moth Bombyx mori, for example)). In such cases the W chromosome is the female-determining and the male is ZZ. (From King & Stansfield, A Dictionary of Genetics, 4th ed)

A characteristic symptom complex.

Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.

The integration of exogenous DNA into the genome of an organism at sites where its expression can be suitably controlled. This integration occurs as a result of homologous recombination.

A metabolic disease characterized by the defective transport of CYSTINE across the lysosomal membrane due to mutation of a membrane protein cystinosin. This results in cystine accumulation and crystallization in the cells causing widespread tissue damage. In the KIDNEY, nephropathic cystinosis is a common cause of RENAL FANCONI SYNDROME.

The percent frequency with which a dominant or homozygous recessive gene or gene combination manifests itself in the phenotype of the carriers. (From Glossary of Genetics, 5th ed)

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.

The health status of the family as a unit including the impact of the health of one member of the family on the family as a unit and on individual family members; also, the impact of family organization or disorganization on the health status of its members.

A group of inherited disorders of the ADRENAL GLANDS, caused by enzyme defects in the synthesis of cortisol (HYDROCORTISONE) and/or ALDOSTERONE leading to accumulation of precursors for ANDROGENS. Depending on the hormone imbalance, congenital adrenal hyperplasia can be classified as salt-wasting, hypertensive, virilizing, or feminizing. Defects in STEROID 21-HYDROXYLASE; STEROID 11-BETA-HYDROXYLASE; STEROID 17-ALPHA-HYDROXYLASE; 3-beta-hydroxysteroid dehydrogenase (3-HYDROXYSTEROID DEHYDROGENASES); TESTOSTERONE 5-ALPHA-REDUCTASE; or steroidogenic acute regulatory protein; among others, underlie these disorders.

Abnormal number or structure of the SEX CHROMOSOMES. Some sex chromosome aberrations are associated with SEX CHROMOSOME DISORDERS and SEX CHROMOSOME DISORDERS OF SEX DEVELOPMENT.

Actual loss of portion of a chromosome.

A rare autosomal recessive disorder of the urea cycle. It is caused by a deficiency of the hepatic enzyme ARGINASE. Arginine is elevated in the blood and cerebrospinal fluid, and periodic HYPERAMMONEMIA may occur. Disease onset is usually in infancy or early childhood. Clinical manifestations include seizures, microcephaly, progressive mental impairment, hypotonia, ataxia, spastic diplegia, and quadriparesis. (From Hum Genet 1993 Mar;91(1):1-5; Menkes, Textbook of Child Neurology, 5th ed, p51)

Determination of the nature of a pathological condition or disease in the postimplantation EMBRYO; FETUS; or pregnant female before birth.

The authorized absence from work of a family member to attend the illness or participate in the care of a parent, a sibling, or other family member. For the care of a parent for a child or for pre- or postnatal leave of a parent, PARENTAL LEAVE is available.

Recording of electric potentials in the retina after stimulation by light.

Systemic lysosomal storage disease marked by progressive physical deterioration and caused by a deficiency of L-sulfoiduronate sulfatase. This disease differs from MUCOPOLYSACCHARIDOSIS I by slower progression, lack of corneal clouding, and X-linked rather than autosomal recessive inheritance. The mild form produces near-normal intelligence and life span. The severe form usually causes death by age 15.

A chloride channel that regulates secretion in many exocrine tissues. Abnormalities in the CFTR gene have been shown to cause cystic fibrosis. (Hum Genet 1994;93(4):364-8)

An enzyme that catalyzes the hydrolysis of terminal, non-reducing alpha-D-galactose residues in alpha-galactosides including galactose oligosaccharides, galactomannans, and galactolipids.

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.

A subtype of HLA-DRB beta chains that includes over 50 allelic variants. The HLA-DRB3 beta-chain subtype is associated with HLA-DR52 serological subtype.

Plasma glycoprotein member of the serpin superfamily which inhibits TRYPSIN; NEUTROPHIL ELASTASE; and other PROTEOLYTIC ENZYMES.

An inherited urea cycle disorder associated with deficiency of the enzyme ORNITHINE CARBAMOYLTRANSFERASE, transmitted as an X-linked trait and featuring elevations of amino acids and ammonia in the serum. Clinical features, which are more prominent in males, include seizures, behavioral alterations, episodic vomiting, lethargy, and coma. (Menkes, Textbook of Child Neurology, 5th ed, pp49-50)

An infant during the first month after birth.

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.

A set of three nucleotides in a protein coding sequence that specifies individual amino acids or a termination signal (CODON, TERMINATOR). Most codons are universal, but some organisms do not produce the transfer RNAs (RNA, TRANSFER) complementary to all codons. These codons are referred to as unassigned codons (CODONS, NONSENSE).

Iron-containing proteins that are widely distributed in animals, plants, and microorganisms. Their major function is to store IRON in a nontoxic bioavailable form. Each ferritin molecule consists of ferric iron in a hollow protein shell (APOFERRITINS) made of 24 subunits of various sequences depending on the species and tissue types.

Receptors on the plasma membrane of nonhepatic cells that specifically bind LDL. The receptors are localized in specialized regions called coated pits. Hypercholesteremia is caused by an allelic genetic defect of three types: 1, receptors do not bind to LDL; 2, there is reduced binding of LDL; and 3, there is normal binding but no internalization of LDL. In consequence, entry of cholesterol esters into the cell is impaired and the intracellular feedback by cholesterol on 3-hydroxy-3-methylglutaryl CoA reductase is lacking.

White blood cells. These include granular leukocytes (BASOPHILS; EOSINOPHILS; and NEUTROPHILS) as well as non-granular leukocytes (LYMPHOCYTES and MONOCYTES).

Methods used to determine individuals' specific ALLELES or SNPS (single nucleotide polymorphisms).

The condition of being heterozygous for hemoglobin S.

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.

The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.

Glycogenosis due to muscle phosphorylase deficiency. Characterized by painful cramps following sustained exercise.

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.

Congenital absence of or defects in structures of the eye; may also be hereditary.

The age, developmental stage, or period of life at which a disease or the initial symptoms or manifestations of a disease appear in an individual.

Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.

The most abundant protein component of HIGH DENSITY LIPOPROTEINS or HDL. This protein serves as an acceptor for CHOLESTEROL released from cells thus promoting efflux of cholesterol to HDL then to the LIVER for excretion from the body (reverse cholesterol transport). It also acts as a cofactor for LECITHIN CHOLESTEROL ACYLTRANSFERASE that forms CHOLESTEROL ESTERS on the HDL particles. Mutations of this gene APOA1 cause HDL deficiency, such as in FAMILIAL ALPHA LIPOPROTEIN DEFICIENCY DISEASE and in some patients with TANGIER DISEASE.

Early pregnancy loss during the EMBRYO, MAMMALIAN stage of development. In the human, this period comprises the second through eighth week after fertilization.

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.

Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.

A method of detecting gene mutation by mixing PCR-amplified mutant and wild-type DNA followed by denaturation and reannealing. The resultant products are resolved by gel electrophoresis, with single base substitutions detectable under optimal electrophoretic conditions and gel formulations. Large base pair mismatches may also be analyzed by using electron microscopy to visualize heteroduplex regions.

Lipid-protein complexes involved in the transportation and metabolism of lipids in the body. They are spherical particles consisting of a hydrophobic core of TRIGLYCERIDES and CHOLESTEROL ESTERS surrounded by a layer of hydrophilic free CHOLESTEROL; PHOSPHOLIPIDS; and APOLIPOPROTEINS. Lipoproteins are classified by their varying buoyant density and sizes.

An autosomal recessive disorder caused by a deficiency of acid beta-glucosidase (GLUCOSYLCERAMIDASE) leading to intralysosomal accumulation of glycosylceramide mainly in cells of the MONONUCLEAR PHAGOCYTE SYSTEM. The characteristic Gaucher cells, glycosphingolipid-filled HISTIOCYTES, displace normal cells in BONE MARROW and visceral organs causing skeletal deterioration, hepatosplenomegaly, and organ dysfunction. There are several subtypes based on the presence and severity of neurological involvement.

An enzyme that specifically cleaves the ester sulfate of iduronic acid. Its deficiency has been demonstrated in Hunter's syndrome, which is characterized by an excess of dermatan sulfate and heparan sulfate. EC 3.1.6.13.

A disease characterized by chronic hemolytic anemia, episodic painful crises, and pathologic involvement of many organs. It is the clinical expression of homozygosity for hemoglobin S.

The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid.

A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.

Created 1 January 1993 as a result of the division of Czechoslovakia into the Czech Republic and Slovakia.

The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.

Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.

Mice which carry mutant genes for neurologic defects or abnormalities.

A family of sterols commonly found in plants and plant oils. Alpha-, beta-, and gamma-isomers have been characterized.

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.

Death of the developing young in utero. BIRTH of a dead FETUS is STILLBIRTH.

Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.

Electrophoresis applied to BLOOD PROTEINS.

A rare, pigmentary, and atrophic autosomal recessive disease. It is manifested as an extreme photosensitivity to ULTRAVIOLET RAYS as the result of a deficiency in the enzyme that permits excisional repair of ultraviolet-damaged DNA.

White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.

Individuals whose ancestral origins are in the continent of Africa.

Membrane glycoproteins consisting of an alpha subunit and a BETA 2-MICROGLOBULIN beta subunit. In humans, highly polymorphic genes on CHROMOSOME 6 encode the alpha subunits of class I antigens and play an important role in determining the serological specificity of the surface antigen. Class I antigens are found on most nucleated cells and are generally detected by their reactivity with alloantisera. These antigens are recognized during GRAFT REJECTION and restrict cell-mediated lysis of virus-infected cells.

The fluid excreted by the SWEAT GLANDS. It consists of water containing sodium chloride, phosphate, urea, ammonia, and other waste products.

Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.

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.

Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.

Cholesterol which is contained in or bound to high-density lipoproteins (HDL), including CHOLESTEROL ESTERS and free cholesterol.

Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.

Structural proteins of the alpha-lipoproteins (HIGH DENSITY LIPOPROTEINS), including APOLIPOPROTEIN A-I and APOLIPOPROTEIN A-II. They can modulate the activity of LECITHIN CHOLESTEROL ACYLTRANSFERASE. These apolipoproteins are low in atherosclerotic patients. They are either absent or present in extremely low plasma concentration in TANGIER DISEASE.

Congenital malformations of the central nervous system and adjacent structures related to defective neural tube closure during the first trimester of pregnancy generally occurring between days 18-29 of gestation. Ectodermal and mesodermal malformations (mainly involving the skull and vertebrae) may occur as a result of defects of neural tube closure. (From Joynt, Clinical Neurology, 1992, Ch55, pp31-41)

A group of disorders which have in common elevations of tyrosine in the blood and urine secondary to an enzyme deficiency. Type I tyrosinemia features episodic weakness, self-mutilation, hepatic necrosis, renal tubular injury, and seizures and is caused by a deficiency of the enzyme fumarylacetoacetase. Type II tyrosinemia features INTELLECTUAL DISABILITY, painful corneal ulcers, and keratoses of the palms and plantar surfaces and is caused by a deficiency of the enzyme TYROSINE TRANSAMINASE. Type III tyrosinemia features INTELLECTUAL DISABILITY and is caused by a deficiency of the enzyme 4-HYDROXYPHENYLPYRUVATE DIOXYGENASE. (Menkes, Textbook of Child Neurology, 5th ed, pp42-3)

Any one of a group of congenital hemolytic anemias in which there is no abnormal hemoglobin or spherocytosis and in which there is a defect of glycolysis in the erythrocyte. Common causes include deficiencies in GLUCOSE-6-PHOSPHATE ISOMERASE; PYRUVATE KINASE; and GLUCOSE-6-PHOSPHATE DEHYDROGENASE.

A retrogressive pathological change in the retina, focal or generalized, caused by genetic defects, inflammation, trauma, vascular disease, or aging. Degeneration affecting predominantly the macula lutea of the retina is MACULAR DEGENERATION. (Newell, Ophthalmology: Principles and Concepts, 7th ed, p304)

A commonly occurring abnormal hemoglobin in which lysine replaces a glutamic acid residue at the sixth position of the beta chains. It results in reduced plasticity of erythrocytes.

The presence of apparently similar characters for which the genetic evidence indicates that different genes or different genetic mechanisms are involved in different pedigrees. In clinical settings genetic heterogeneity refers to the presence of a variety of genetic defects which cause the same disease, often due to mutations at different loci on the same gene, a finding common to many human diseases including ALZHEIMER DISEASE; CYSTIC FIBROSIS; LIPOPROTEIN LIPASE DEFICIENCY, FAMILIAL; and POLYCYSTIC KIDNEY DISEASES. (Rieger, et al., Glossary of Genetics: Classical and Molecular, 5th ed; Segen, Dictionary of Modern Medicine, 1992)

The relative amount by which the average fitness of a POPULATION is lowered, due to the presence of GENES that decrease survival, compared to the GENOTYPE with maximum or optimal fitness. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)

The range or frequency distribution of a measurement in a population (of organisms, organs or things) that has not been selected for the presence of disease or abnormality.

The entity of a developing mammal (MAMMALS), generally from the cleavage of a ZYGOTE to the end of embryonic differentiation of basic structures. For the human embryo, this represents the first two months of intrauterine development preceding the stages of the FETUS.

Transport proteins that carry specific substances in the blood or across cell membranes.

Mapping of the homothallic genes, HM alpha and HMa, in Saccharomyces yeasts. (1/10346)

Two of the three homothallic genes, HM alpha and HMa, showed direct linkage to the mating-type locus at approximately 73 and 98 strans (57 and 65 centimorgans [cM], respectively, whereas, the other, HO, showed no linkage to 25 standard markers distributed over 17 chromosomes including the mating-type locus. To determine whether the HM alpha and HMa loci located on the left or right side of the mating-type locus, equations for three factor analysis of three linked genes were derived. Tetrad data were collected and were compared with expected values by chi 2 statistics. Calculations indicated that the HM alpha gene is probably located on the right arm at 95 strans (65 cM) from the centromere and the HMa locus at approximately 90 strans (64 cM) on the left arm of chromosome III. (+info)

The Drosophila kismet gene is related to chromatin-remodeling factors and is required for both segmentation and segment identity. (2/10346)

The Drosophila kismet gene was identified in a screen for dominant suppressors of Polycomb, a repressor of homeotic genes. Here we show that kismet mutations suppress the Polycomb mutant phenotype by blocking the ectopic transcription of homeotic genes. Loss of zygotic kismet function causes homeotic transformations similar to those associated with loss-of-function mutations in the homeotic genes Sex combs reduced and Abdominal-B. kismet is also required for proper larval body segmentation. Loss of maternal kismet function causes segmentation defects similar to those caused by mutations in the pair-rule gene even-skipped. The kismet gene encodes several large nuclear proteins that are ubiquitously expressed along the anterior-posterior axis. The Kismet proteins contain a domain conserved in the trithorax group protein Brahma and related chromatin-remodeling factors, providing further evidence that alterations in chromatin structure are required to maintain the spatially restricted patterns of homeotic gene transcription. (+info)

Mrj encodes a DnaJ-related co-chaperone that is essential for murine placental development. (3/10346)

We have identified a novel gene in a gene trap screen that encodes a protein related to the DnaJ co-chaperone in E. coli. The gene, named Mrj (mammalian relative of DnaJ) was expressed throughout development in both the embryo and placenta. Within the placenta, expression was particularly high in trophoblast giant cells but moderate levels were also observed in trophoblast cells of the chorion at embryonic day 8.5, and later in the labyrinth which arises from the attachment of the chorion to the allantois (a process called chorioallantoic fusion). Insertion of the ROSAbetageo gene trap vector into the Mrj gene created a null allele. Homozygous Mrj mutants died at mid-gestation due to a failure of chorioallantoic fusion at embryonic day 8.5, which precluded formation of the mature placenta. At embryonic day 8.5, the chorion in mutants was morphologically normal and expressed the cell adhesion molecule beta4 integrin that is known to be required for chorioallantoic fusion. However, expression of the chorionic trophoblast-specific transcription factor genes Err2 and Gcm1 was significantly reduced. The mutants showed no abnormal phenotypes in other trophoblast cell types or in the embryo proper. This study indicates a previously unsuspected role for chaperone proteins in placental development and represents the first genetic analysis of DnaJ-related protein function in higher eukaryotes. Based on a survey of EST databases representing different mouse tissues and embryonic stages, there are 40 or more DnaJ-related genes in mammals. In addition to Mrj, at least two of these genes are also expressed in the developing mouse placenta. The specificity of the developmental defect in Mrj mutants suggests that each of these genes may have unique tissue and cellular activities. (+info)

Identification of sonic hedgehog as a candidate gene responsible for the polydactylous mouse mutant Sasquatch. (4/10346)

The mouse mutants of the hemimelia-luxate group (lx, lu, lst, Dh, Xt, and the more recently identified Hx, Xpl and Rim4; [1] [2] [3] [4] [5]) have in common preaxial polydactyly and longbone abnormalities. Associated with the duplication of digits are changes in the regulation of development of the anterior limb bud resulting in ectopic expression of signalling components such as Sonic hedgehog (Shh) and fibroblast growth factor-4 (Fgf4), but little is known about the molecular causes of this misregulation. We generated, by a transgene insertion event, a new member of this group of mutants, Sasquatch (Ssq), which disrupted aspects of both anteroposterior (AP) and dorsoventral (DV) patterning. The mutant displayed preaxial polydactyly in the hindlimbs of heterozygous embryos, and in both hindlimbs and forelimbs of homozygotes. The Shh, Fgf4, Fgf8, Hoxd12 and Hoxd13 genes were all ectopically expressed in the anterior region of affected limb buds. The insertion site was found to lie close to the Shh locus. Furthermore, expression from the transgene reporter has come under the control of a regulatory element that directs a pattern mirroring the endogenous expression pattern of Shh in limbs. In abnormal limbs, both Shh and the reporter were ectopically induced in the anterior region, whereas in normal limbs the reporter and Shh were restricted to the zone of polarising activity (ZPA). These data strongly suggest that Ssq is caused by direct interference with the cis regulation of the Shh gene. (+info)

Factor VII deficiency rescues the intrauterine lethality in mice associated with a tissue factor pathway inhibitor deficit. (5/10346)

Mice doubly heterozygous for a modified tissue factor pathway inhibitor (TFPI) allele (tfpi delta) lacking its Kunitz-type domain-1 (TFPI+/delta) and for a deficiency of the factor VII gene (FVII+/-) were mated to generate 309 postnatal and 205 embryonic day 17.5 (E17. 5) offspring having all the predicted genotypic combinations. Progeny singly homozygous for the tfpidelta modification but with the wild-type fVII allele (FVII+/+/TFPIdelta/delta), and mice singly homozygous for the fVII deficiency and possessing the wild-type tfpi allele (FVII-/-/TFPI+/+), displayed previously detailed phenotypes (i.e., a high percentage of early embryonic lethality at E9.5 or normal development with severe perinatal bleeding, respectively). Surprisingly, mice of the combined FVII-/-/TFPIdelta/delta genotype were born at the expected mendelian frequency but suffered the fatal perinatal bleeding associated with the FVII-/- genotype. Mice carrying the FVII+/-/TFPIdelta/delta genotype were also rescued from the lethality associated with the FVII+/+/TFPIdelta/delta genotype but succumbed to perinatal consumptive coagulopathy. Thus, the rescue of TFPIdelta/delta embryos, either by an accompanying homozygous or heterozygous FVII deficiency, suggests that diminishment of FVII activity precludes the need for TFPI-mediated inhibition of the FVIIa/tissue factor coagulation pathway during embryogenesis. Furthermore, the phenotypes of these combined deficiency states suggest that embryonic FVII is produced in mice as early as E9.5 and that any level of maternal FVII in early-stage embryos is insufficient to cause a coagulopathy in TFPIdelta/delta mice. (+info)

Loss-of-function mutations in the rice homeobox gene OSH15 affect the architecture of internodes resulting in dwarf plants. (6/10346)

The rice homeobox gene OSH15 (Oryza sativa homeobox) is a member of the knotted1-type homeobox gene family. We report here on the identification and characterization of a loss-of-function mutation in OSH15 from a library of retrotransposon-tagged lines of rice. Based on the phenotype and map position, we have identified three independent deletion alleles of the locus among conventional morphological mutants. All of these recessive mutations, which are considered to be null alleles, exhibit defects in internode elongation. Introduction of a 14 kbp genomic DNA fragment that includes all exons, introns and 5'- and 3'- flanking sequences of OSH15 complemented the defects in internode elongation, confirming that they were caused by the loss-of-function of OSH15. Internodes of the mutants had abnormal-shaped epidermal and hypodermal cells and showed an unusual arrangement of small vascular bundles. These mutations demonstrate a role for OSH15 in the development of rice internodes. This is the first evidence that the knotted1-type homeobox genes have roles other than shoot apical meristem formation and/or maintenance in plant development. (+info)

Thyroid hormone effects on Krox-24 transcription in the post-natal mouse brain are developmentally regulated but are not correlated with mitosis. (7/10346)

Krox-24 (NGFI-A, Egr-1) is an immediate-early gene encoding a zinc finger transcription factor. As Krox-24 is expressed in brain areas showing post-natal neurogenesis during a thyroid hormone (T3)-sensitive period, we followed T3 effects on Krox-24 expression in newborn mice. We analysed whether regulation was associated with changes in mitotic activity in the subventricular zone and the cerebellum. In vivo T3-dependent Krox-24 transcription was studied by polyethylenimine-based gene transfer. T3 increased transcription from the Krox-24 promoter in both areas studied at post-natal day 2, but was without effect at day 6. An intact thyroid hormone response element (TRE) in the Krox-24 promoter was necessary for these inductions. These stage-dependent effects were also seen in endogenous Krox-24 mRNA levels: activation at day 2 and no effect at day 6. Moreover, similar results were obtained by examining beta-galactosidase expression in heterozygous mice in which one allele of the Krox-24 gene was disrupted with an inframe Lac-Z insertion. However, bromodeoxyuridine incorporation showed mitosis to continue through to day 6. We conclude first, that T3 activates Krox-24 transcription during early post-natal mitosis but that this effect is extinguished as development proceeds and second, loss of T3-dependent Krox-24 expression is not correlated with loss of mitotic activity. (+info)

Angiotensinogen gene polymorphisms M235T/T174M: no excess transmission to hypertensive Chinese. (8/10346)

The gene encoding angiotensinogen (AGT) has been widely studied as a candidate gene for hypertension. Most studies to date have relied on case-control analysis to test for an excess of AGT variants among hypertensive cases compared with normotensive controls. However, with this design, nothing guarantees that a positive finding is due to actual allelic association as opposed to an inappropriate control population. To avoid this difficulty in our study of essential hypertension in Anqing, China, we tested AGT variants using the transmission/disequilibrium test, a procedure that bypasses the need for a control sample by testing for excessive transmission of a genetic variant from parents heterozygous for that variant. We analyzed two AGT polymorphisms, M235T and T174M, which have been associated with essential hypertension in whites and Japanese, using data on 335 hypertensive subjects from 315 nuclear families and their parents. Except in the group of subjects younger than 25 years, M235 and T174 were the more frequently transmitted alleles. We found that 194 parents heterozygous for M235T transmitted M235 106 times (P=0.22) and that 102 parents heterozygous for T174M transmitted T174 60 times (P=0.09). Stratifying offspring by gender, M235 and T174 were transmitted 60 of 106 times (P=0.21) and 44 of 75 times (P=0.17), respectively, in men, and 46 of 88 times (P=0.75) and 16 of 27 times (P=0.44), respectively, in women. Our results were also negative in all age groups and for the affected offspring with blood pressure values >/=160/95 mm Hg. Thus, this study provides no evidence that either allele of M235T or T174M contributes to hypertension in this Chinese population. (+info)

Heterozygote advantage[edit]. Sickle-shaped red blood cells. This non-lethal condition in heterozygotes is maintained by ... Main article: Heterozygote advantage. In heterozygote advantage, or heterotic balancing selection, an individual who is ... The heterozygote has a permanent advantage (a higher fitness) wherever malaria exists.[4][5] Maintenance of the HgbS allele ... The heterozygote is resistant to the malarial parasite which kills a large number of people each year. This is an example of ...

https://en.wikipedia.org/wiki/Balancing_selection

Heterozygote advantage[change , change source]. Sickle-shaped red blood cells. This non-lethal condition in heterozygotes is ... Main page: heterozygote advantage. In heterozygote advantage, or heterotic balancing selection, an individual who is ... The heterozygote is resistant to the malarial parasite which kills a large number of people each year. The heterozygote ... This usually happens when the heterozygote for a gene has a higher relative fitness than the homozygote. In this way genetic ...

https://simple.wikipedia.org/wiki/Balancing_selection

When the new allele is created, a heterozygote containing the newly created allele as well as the original will express the new ... "Compound heterozygote". MedTerms. New York: WebMD. 14 June 2012. Archived from the original on 4 March 2016. Retrieved 9 ... confers HIV resistance to homozygotes and delays AIDS onset in heterozygotes. One possible explanation of the etiology of the ...

https://en.wikipedia.org/wiki/Mutation

Compound heterozygotes are often observed only through subclinical symptoms such as excess iron. Disease is rarely observed in ... This means that many cases of disease arise in individuals who have two unrelated alleles, who technically are heterozygotes, ... As a result, compound heterozygotes often become ill later in life, with less severe symptoms. Although compound heterozygosity ... Anderson JA, Fisch R, Miller E, Doeden D (Mar 1966). "Atypical phenylketonuric heterozygote. Deficiency in phenylalanine ...

https://en.wikipedia.org/wiki/Compound_heterozygosity

Woolf, LI (1986). "The heterozygote advantage in phenylketonuria". American Journal of Human Genetics. 38 (5): 773-5. PMC ...

https://en.wikipedia.org/wiki/Genetic_disorder

The heterozygote test is used for the early detection of recessive hereditary diseases, allowing for couples to determine if ... "Heterozygote test / Screening programmes - DRZE". Drze.de. Retrieved 19 October 2017. "Fatal Gift: Jewish Intelligence and ... although not influencing the prevalence of heterozygote carriers of those diseases. The elevated prevalence of certain ...

https://en.wikipedia.org/wiki/Eugenics

Overdominance occurs if the heterozygote phenotype has a fitness advantage over both homozygotes (heterozygote advantage, ... Hence, homozygote and heterozygote genotypes for the sickle-cell disease allele show malaria resistance, while the homozygote ... As a consequence, the heterozygote genotype is selectively favored in areas with a high incidence of malaria. If an allele ... overdominance caused by heterozygote advantage; and directional selective sweeps near an advantageous mutation. Theories of ...

https://en.wikipedia.org/wiki/Host–parasite_coevolution

Woolf LI (May 1986). "The heterozygote advantage in phenylketonuria". American Journal of Human Genetics. 38 (5): 773-5. PMC ... being a heterozygote is advantageous. The PAH gene is located on chromosome 12 in the bands 12q22-q24.2. As of 2000, around 400 ...

https://en.wikipedia.org/wiki/Phenylketonuria

Furthermore, many colonies show heterozygote excesses. This led researchers to conclude that outbreeding is common in the S. ...

https://en.wikipedia.org/wiki/Synalpheus_regalis

One of the first genetic testing programs to identify heterozygote carriers of a genetic disorder was a program aimed at ... However, most populations contain hundreds of alleles that could potentially cause disease and most people are heterozygotes ... This effect is called heterozygote advantage. Familial dysautonomia (Riley-Day syndrome), which causes vomiting, speech ... effect of drift on decay of linkage disequilibrium and evidence for heterozygote selection". Blood Cells, Molecules & Diseases ...

https://en.wikipedia.org/wiki/Medical_genetics_of_Jews

Heterozygotes are normal. Consanguinity is common. The failure of amino-acid transport was reported in 1960 from the increased ...

https://en.wikipedia.org/wiki/Hartnup_disease

Heterozygote advantage. References[edit]. *^ George Harrison Shull (1948). "What Is "Heterosis"?". Genetics. 33 (5): 439-446. ... Main articles: Heterozygote advantage, Histone H3, and microRNA. Since the early 1900s, two competing genetic hypotheses, not ... Certain combinations of alleles that can be obtained by crossing two inbred strains are advantageous in the heterozygote. The ... the effect of the alleles and the degree to which alleles are expressed in heterozygotes.[5] ...

https://en.wikipedia.org/wiki/Heterosis

Amos W, Sawcer SJ, Feakes RW, Rubinsztein DC (August 1996). "Microsatellites show mutational bias and heterozygote instability ...

https://en.wikipedia.org/wiki/Microsatellite

Most heterozygotes are asymptomatic. Symptoms do not occur unless FECH activity is less than 30% of normal, but such low levels ...

https://en.wikipedia.org/wiki/Erythropoietic_protoporphyria

Heterozygotes (carriers) are asymptomatic. Sibs of a proband At conception, each sibling of an affected individual has a 25% ... Once an at-risk sibling is known to be unaffected, the risk of his/her being a carrier is 2/3. Heterozygotes (carriers) are ... Parents of a proband The parents of an affected individual are obligate heterozygotes and therefore carry one mutant allele. ... Offspring of a proband Offspring of a proband are obligate heterozygotes and will therefore carry one mutant allele. In ...

https://en.wikipedia.org/wiki/Bilateral_frontoparietal_polymicrogyria

Sickle-cell heterozygote frequencies up to 20% also occur in pockets of India and Greece that were formerly highly malarious. ... concurrent polymorphisms - double heterozygotes for HbS and β-thalassemia, and for HbS and HbC, suffer from variant forms of ... This has led to the hypothesis that while homozygotes for the sickle cell gene suffer from disease, heterozygotes might be ... If the frequency of the heterozygote is 0.40 the sickle-cell gene frequency (q) can be calculated from the Hardy-Weinberg ...

https://en.wikipedia.org/wiki/Genetic_Resistance_to_Malaria

DQ2.5/DQ8 HeterozygotesEdit. The distribution of this phenotype is largely the result of admixtures between peoples of eastern ... New evidence is showing an increased risk for late onset Type 1 diabetes in Heterozygotes (which includes ambiguous Type I/Type ... Diseases that appear to be increased in Heterozygotes are Celiac Disease and Type 1 Diabetes. ... Such a person is a double heterozygote for these genes, for DQ the most popular situation. If a person carries haplotypes -A-B ...

https://en.m.wikipedia.org/wiki/HLA-DQ

Woolf, L. I. "The heterozygote advantage in phenylketonuria." (Letter) Am. J. Hum. Genet. 38: 773-775, 1986. Extensive ...

https://en.wikipedia.org/wiki/Ochratoxin

... homozygote and also the heterozygote is normal (though heterozygote individuals will suffer periodic problems). The sickle-cell ... The heterozygote has a permanent advantage (a higher fitness) so long as malaria exists; and it has existed as a human parasite ... Because the heterozygote survives, so does the HgbS allele survive at a rate much higher than the mutation rate. The Duffy ... Now, assuming equal viability of the genotypes 1,209 heterozygotes would be expected, so the field results do not suggest any ...

https://en.wikipedia.org/wiki/List_of_polymorphisms

Heterozygotes (Aa) can arise in two ways: when p male (A allele) randomly fertilize q female (a allele) gametes, and vice versa ... Heterozygotes can arise only from the allozygous component, and its frequency in the sample bulk is just (1-f): hence this must ... The heterozygote deviation from the same midpoint can be named "d", this being the "dominance" effect referred to above. The ... Previously, it was noted that the decline in heterozygotes was f ( 2 p 0 q 0 ) {\textstyle f\left(2p_{0}q_{0}\right)} . This ...

https://en.wikipedia.org/wiki/Quantitative_genetics

Now, assuming equal viability of the genotypes 1,209 heterozygotes would be expected, so the field results do not suggest any ... This is sufficient to maintain the system despite the fact that in this case the heterozygote has slightly lower viability. ... and the heterozygote (medionigra). It was studied there by E. B. Ford, and later by P. M. Sheppard and their co-workers over ...

https://en.wikipedia.org/wiki/Polymorphism_in_Lepidoptera

However, one study used ERG findings to diagnose all the homozygous Lp subjects with CSNB, while all heterozygotes and non-Lp ... A proposed gene, PATN-1, may be responsible for the most familiar expressions of white: heterozygotes possessing common-size " ... While both heterozygous and homozygous Lp horses possess the aforementioned characteristics, heterozygotes and homozygotes ... A heterozygote may eventually show conspicuous leopard spots. Base colors are overlain by various spotting patterns, which are ...

https://en.wikipedia.org/wiki/Leopard_complex

However, other studies are using the heterozygote mutant. The maize genome is 80% transposons so DDM1 function is quite ...

https://en.wikipedia.org/wiki/Decrease_in_DNA_Methylation_I_(DDM1)

In addition, heterozygote mutants displayed premature hair follicle exogen. GRCh38: Ensembl release 89: ENSG00000037474 - ...

https://en.wikipedia.org/wiki/NSUN2

Unusual gene dosage effect in heterozygotes". Hum. Genet. 77 (2): 168-71. doi:10.1007/BF00272386. PMID 3308682. S2CID 19941299 ... 1999). "Dominant negative allele (N47D) in a compound heterozygote for a variant of 6-pyruvoyltetrahydropterin synthase ...

https://en.wikipedia.org/wiki/PTS_(gene)

Merle is actually a heterozygote of an incompletely dominant gene. If two such dogs are mated, on the average one quarter of ...

https://en.wikipedia.org/wiki/Merle_(dog_coat)

... mis-segregation from multivalents in interchange heterozygotes." Incidences of polysomy have been identified in many species of ...

https://en.wikipedia.org/wiki/Polysomy

Heterozygotes show locomotion defects with neuronal loss. Homozygotes are unable to feed and move and die within 24 hours of ...

https://en.wikipedia.org/wiki/Elizabeth_Fisher_(neuroscientist)

Such females are known as manifesting heterozygotes. Examples of X-linked disorders include ornithine transcarbamylase ... Other articles where Manifesting heterozygote is discussed: metabolic disease: Inheritance: ... affect females who are "manifesting heterozygotes" (see the section Inheritance), presenting with severe disease during infancy ... Such females are known as manifesting heterozygotes. Examples of X-linked disorders include ornithine transcarbamylase ...

https://www.britannica.com/science/manifesting-heterozygote

A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the ... Heterozygote advantage is a major underlying mechanism for heterosis, or "hybrid vigor", which is the improved or increased ... The heterozygote expressed none of the disadvantages of homozygotes, yet gained improved viability. The homozygote wild type ... The specific case of heterozygote advantage due to a single locus is known as overdominance. Overdominance is a condition in ...

https://en.wikipedia.org/wiki/Heterozygote_advantage

Manifesting heterozygote definition at Dictionary.com, a free online dictionary with pronunciation, synonyms and translation. ... Words nearby manifesting heterozygote. manifestative, manifest content, Manifest Destiny, manifest function, manifest hyperopia ...

https://www.dictionary.com/browse/manifesting-heterozygote

Heterozygotes definition, a hybrid containing genes for two unlike forms of a characteristic, and therefore not breeding true ... heterozygotes in Medicine Expand. heterozygote het·er·o·zy·gote (hětə-rō-zīgōt). n. An organism that has different alleles ... Some are probably matings of two heterozygotes, others of two recessives, and others still of a recessive with a heterozygote. ... Do the 4-toed heterozygotes produce a larger proportion of imperfect dominants in F2 than the 5-toed heterozygotes? ...

http://www.dictionary.com/browse/heterozygotes

A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the ... The specific case of heterozygote advantage due to a single locus is known as overdominance.[1][2] Overdominance is a condition ... Heterozygote advantage is a major underlying mechanism for heterosis, or "hybrid vigor", which is the improved or increased ... The first experimental confirmation of heterozygote advantage was with Drosophila melanogaster, a fruit fly that has been a ...

https://en.m.wikipedia.org/wiki/Heterozygous_advantage

(2005) Anton et al. Cytogenetic and Genome Research. The risk of producing unbalanced gametes in heterozygous inversion carriers mostly depends on the occurrence of recombination events within the inverted segment. Recombination determines the possib...

https://www.mendeley.com/research-papers/sperm-studies-heterozygote-inversion-carriers-review/

THE EFFECTS OF INBREEDING AT LOCI WITH HETEROZYGOTE ADVANTAGE Message Subject (Your Name) has forwarded a page to you from ... THE EFFECTS OF INBREEDING AT LOCI WITH HETEROZYGOTE ADVANTAGE. W. G. Hill and Alan Robertson ... THE EFFECTS OF INBREEDING AT LOCI WITH HETEROZYGOTE ADVANTAGE. W. G. Hill and Alan Robertson ... THE EFFECTS OF INBREEDING AT LOCI WITH HETEROZYGOTE ADVANTAGE. W. G. Hill and Alan Robertson ...

https://www.genetics.org/content/60/3/615

How many of these genes are undergoing heterozygote advantage selection is only beginning to be known. Initial genomic surveys ... Unless further studies provide large numbers of loci with heterozygote advantage, it appears that loci with heterozygote ... What is the evidence for heterozygote advantage selection? Trends Ecol Evol. 2012 Dec;27(12):698-704. doi: 10.1016/j.tree. ... This is not to say that some heterozygote advantage loci do not have important adaptive functions, but that their role in ...

https://pubmed.ncbi.nlm.nih.gov/22975220/?dopt=Abstract

Here we report five new examples of heterozygote advantage, based around polymorphisms in the BMP15 and GDF9 genes that affect ... These are amongst the most frequent and compelling examples of heterozygote advantage yet described and the first documented ... there remain few examples that fit the criteria for heterozygote advantage, all of which are associated with disease resistance ... which are amongst the highest yet reported for a polymorphism maintained by heterozygote advantage. ...

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0000125

Subject: what is the level of gene expression in a homozygote and heterozygote?. Date: Sat Jul 25 19:00:38 1998. Posted by ... Re: what is the level of gene expression in a homozygote and heterozygote? Current Queue , Current Queue for Genetics , ... I would like to know about the level of gene expression in homozygote and heterozygote with respect to a transgenic loci and a ... wild type loci? I am under the impression that the level of gene expression in a homozygote and a heterozygote in the case of a ...

http://www.madsci.org/posts/archives/1998-10/904867873.Ge.q.html

... Date: Mon Aug 31 15:54:48 1998. Posted By: Wayde ... A heterozygote would show levels of expression of 1(A) + 1(a), and a homozygote for a would be 2(a). This should hold true for ...

http://www.madsci.org/posts/archives/1998-10/904867873.Ge.r.html

Page T., Bakay B., Nyhan W.L. (1984) Detection of Hypoxanthine Guanine Phosphoribosyl Transferase Heterozygotes by Thin Layer ... Detection of Hypoxanthine Guanine Phosphoribosyl Transferase Heterozygotes by Thin Layer Chromatography and Autoradiography. ... Such mosaicism has been demonstrated in populations of cultured fibroblasts and in hair root follicles of heterozygotes (4,5). ...

https://link.springer.com/chapter/10.1007/978-1-4684-4553-4_52

HLA and HIV-1: Heterozygote Advantage and B*35-Cw*04 Disadvantage ... HLA and HIV-1: Heterozygote Advantage and B*35-Cw*04 ... HLA and HIV-1: Heterozygote Advantage and B*35-Cw*04 Disadvantage ... HLA and HIV-1: Heterozygote Advantage and B*35-Cw*04 ...

https://science.sciencemag.org/content/283/5408/1748/tab-article-info

On the Potential for Estimating the Effective Number of Breeders From Heterozygote-Excess in Progeny. A. I. Pudovkin, D. V. ... On the Potential for Estimating the Effective Number of Breeders From Heterozygote-Excess in Progeny. A. I. Pudovkin, D. V. ... On the Potential for Estimating the Effective Number of Breeders From Heterozygote-Excess in Progeny. A. I. Pudovkin, D. V. ... In computer simulations, heterozygote excesses for 30 unlinked loci having various numbers of alleles and allele-frequency ...

https://www.genetics.org/content/144/1/383

... it takes longer for escape mutants to arise in heterozygotes than in homozygous individuals. In any case, that heterozygotes ... 1, E and F, and Table 2). The results affirm the strong association of HLA-B*35/+ heterozygotes (+ indicates any HLA-B allele ... RH and P values for the two groups are given as a comparison of homozygotes with heterozygotes at all three loci. Influence of ... A parsimonious explanation for this finding is that, overall, heterozygotes present a broader range of HIV-1 peptides than do ...

https://science.sciencemag.org/content/283/5408/1748?ijkey=9a491a6b8881ccf25cacf18a3e2fdac126c4b5cd&keytype2=tf_ipsecsha

Phenylbutyrate/Genistein Duotherapy in Delta F508-Heterozygotes (for Cystic Fibrosis). The safety and scientific validity of ...

https://clinicaltrials.gov/ct2/show/NCT00590538?term=phenylbutyrate&rank=11

A mutant with a heterozygote disadvantage can be maintained in a popul...,Mutants,with,heterozygote,disadvantage,can,prevent, ... Mutants with a heterozygote disadvantage, as it is known, reduce the evolutionary fitness of their carriers to varying degrees ... A mutant with a heterozygote disadvantage can be maintained in a population if it occurs frequently enough for sufficient ... The researchers then analyzed computer-based simulations showing the effect of mutants with heterozygote disadvantage on two ...

http://www.bio-medicine.org/biology-news-1/Mutants-with-heterozygote-disadvantage-can-prevent-spread-of-transgenic-animals-22539-1/

Iammarino, R. M., Wagener, D., & Allen, R. C. (1980). Transmission of Z Allele from Heterozygotes for Alpha-1-Antitrypsin ... Transmission of Z Allele from Heterozygotes for Alpha-1-Antitrypsin Deficiency - Reply. ...

https://www.rti.org/publication/transmission-z-allele-heterozygotes-alpha-1-antitrypsin-deficiency-reply

Two brothers with XP with cancers and neurodegeneration are compound heterozygotes for XPD R683W and an in-frame deletion of 1 ... 3 C). Together, these results indicate that the XPD mutations found in XP patients who are compound heterozygotes for R683W and ... Both XPD alleles contribute to the phenotype of compound heterozygote xeroderma pigmentosum patients. Takahiro Ueda, Emmanuel ... It should be noted that expression of these genes in cells from the compound heterozygote XPD/R683W patients (XP34BE, XP29BE, ...

http://jem.rupress.org/content/206/13/3031

In six controls (13 percent) and in 12 of 19 (63 percent) A-T heterozygotes, the ... heterozygotes was performed. The distribution of chromatid breaks induced in the late G2 portion of the cell cycle by 60 cGy of ... In six controls (13 percent) and in 12 of 19 (63 percent) A-T heterozygotes, the yields of X-ray-induced breaks observed were ... However, lymphocytes from A-T heterozygotes sensitive to the induction of chromatid breaks by 60 cGy did not contain increased ...

https://www.cdc.gov/niosh/nioshtic-2/20000997.html

Impact of iron deficiency on hemoglobin A2% in obligate β-thalassemia heterozygotes.. [P Sharma, R Das, A Trehan, D Bansal, S ...

https://www.sigmaaldrich.com/catalog/papers/24754744

Of all breast cancers in the United States, 6.6% may occur in women who are A-T heterozygotes. This proportion is several fold ... There were 33 women with breast cancer who could be genotyped; 25 of these were A-T heterozygotes, compared to an expected 14.9 ... Molecular genotyping shows that ataxia-telangiectasia heterozygotes are predisposed to breast cancer Cancer Genet Cytogenet. ... The hypothesis that A-T heterozygotes are predisposed to breast cancer was tested by the unbiased statistically powerful index- ...

https://pubmed.ncbi.nlm.nih.gov/8976369/?dopt=Abstract

Author SummaryAn individuals genetic profile can play a role in defining their natural skills and talents. The canine species presents an excellent system in which to find such associative genes. The purebred dog has a long history of selective breeding, which has produced specific breeds of extraordinary strength, intelligence, and speed. We have discovered a mutation in the canine myostatin gene, a negative regulator of muscle mass, which affects muscle composition, and hence racing speed, in whippets. Dogs that possess a single copy of this mutation are more muscled than normal and are among the fastest dogs in competitive racing events. However, dogs with two copies of the same mutation are grossly overmuscled, superficially resembling double-muscled cattle known to possess similar mutations. This result is the first to quantitatively link a mutation in the myostatin gene to athletic performance. Further, it emphasizes what is sure to be a growing area of research for performance-enhancing

http://journals.plos.org/plosgenetics/article/related?id=10.1371/journal.pgen.0030079&imageURI=info:doi/10.1371/journal.pgen.0030079.g004

In conclusion, the CP parameters and SOD1 activity are within the normal range in Icelandic heterozygotes for WD, although with ... This may indicate subclinical copper retention in the heterozygotes, but a bigger study group is needed to confirm this. ... In twenty healthy Icelandic heterozygotes for WD and their age- and gender-matched controls, copper concentration in plasma, ... There was no significant difference in these parameters between the heterozygotes and the controls, although an inclination ...

https://www.dovepress.com/ceruloplasmin-and-superoxide-dismutase-sod1-in-heterozygotes-for-wilso-peer-reviewed-article-NDT

Increased frequency of CCR-5 delta 32 heterozygotes among long-term non-progressors with HIV-1 infection. The Australian Long- ...

https://www.ncbi.nlm.nih.gov/pubmed/9412701?dopt=Abstract

... of the heterozygote pups when the heterozygote parents were fed standard diet (Table 1), the loss of heterozygote pups appears ... The number of heterozygotes in these litters was 10% less than that of WT, representing a loss of 60% of the heterozygotes. In ... To determine whether the loss of heterozygote F2 progeny in F1 heterozygote matings described above (Table 1 and Fig. 2 A) ... Analysis of the breeding behavior of F1 Fasn heterozygotes. F1 heterozygotes were either interbred or bred with WT C57/129 ...

https://www.pnas.org/content/100/11/6358

It is well-known that the variance in heterozygote balance increases as the amount of DNA is reduced. Surprisingly the ... Characterization of degradation and heterozygote balance by simulation of the forensic DNA analysis process. Hansson, Nils ... Simulations suggest that pristine diluted DNA is an acceptable approximation in validations to infer heterozygote balance. ... and PCR efficiency on the heterozygote balance of a range of diploid and haploid cells. Reducing either parameters introduces ...

https://www.duo.uio.no/handle/10852/55185

... 26/11/2018. ... An excess of heterozygotes (in five out of the eight loci genotyped) was found, which suggests a positive selection mechanism ... while heterozygote selection would help maintain some genetic diversity in the populations. S. chupachups has been reported to ... for heterozygotes. The relatively high rates of asexual reproduction may be the result of adaptation to the environmental ...

http://www.ceab.csic.es/es/publication/asexual-reproduction-and-heterozygote-selection-in-an-antarctic-demosponge-stylocordyla-chupachus-suberitida/

The mean value for MCV was lower among the VHLR200W heterozygotes (P=0.033) and the white blood cell counts were higher (P= ... The prevalence of anemia was 15% in the VHLR200W heterozygotes and 34% in the controls (P=0.061 by Pearsons χ2 test). In a ... It seems possible that the observed lower risk for anemia in VHLR200W heterozygotes may be due to a mild increase in HIF ... Mild anemia was present in 15% of VHLR200W heterozygotes and 34% of controls without a mutated VHL allele. By multivariate ...

http://www.haematologica.org/content/96/9/1371

Heterozygotes for the disease are usually identified by their relatively low ratio of heat-labile HEX A to total hexosaminidase ... Heterozygote Detection / methods*. Hexosaminidase A. Hexosaminidases / blood*. Humans. Isoenzymes / blood*. Male. Pregnancy. ... Heterozygotes for the disease are usually identified by their relatively low ratio of heat-labile HEX A to total hexosaminidase ... During pregnancy an intermediate isoenzyme (HEX I) increases in activity in serum and obscures the heterozygote status. HEX I ...

http://www.biomedsearch.com/nih/Radioimmunoassay-heat-denaturation-enzyme-assay/6453673.html

In a classic study on the ebony mutation, Kalmus demonstrated how polymorphism can persist in a population through heterozygote advantage. (wikipedia.org)
This mutation, which at first glance appeared to be harmful, conferred enough of an advantage to heterozygotes to make it beneficial, so that it remained at dynamic equilibrium in the gene pool. (wikipedia.org)
Many XP patients are compound heterozygotes with a "causative" XPD point mutation R683W and different second mutant alleles, considered "null alleles. (rupress.org)
Because the mutation persists from an ancient origin, we hypothesized that there is a heterozygote advantage. (haematologica.org)
Given a negative selection for VHL R200W homozygotes, the mutation should be associated with some type of heterozygote advantage, albeit slight. (haematologica.org)
Whether olfaction differs between Parkin mutation heterozygotes and carriers of 2 Parkin mutations (compound heterozygotes) is unknown. (elsevier.com)
Methods: We administered the University of Pennsylvania Smell Identification Test (UPSIT) to 44 probands in the Consortium on Risk for Early-Onset Parkinson Disease study with PD onset ≤50 years (10 Parkin mutation heterozygotes, 9 compound heterozygotes, 25 noncarriers) and 80 of their family members (18 heterozygotes, 2 compound heterozygotes, 60 noncarriers). (elsevier.com)
Conclusion: Olfaction is significantly reduced among Parkin mutation heterozygotes with PD but not among their heterozygous relatives without PD. (elsevier.com)
Further research is required to assess whether these findings reflect different neuropathology in Parkin mutation heterozygotes and compound heterozygotes. (elsevier.com)
The aim of this study was to determine whether any relationship exists between the severity of mutation of the phenylalanine hydroxylase (PAH) gene and the plasma concentrations of phenylalanine (Phe) and tyrosine (Tyr) under fasting and semifasting conditions among heterozygotes in a matched case-control study. (elsevier.com)
Heterozygotes carrying a severe mutation showed semifasting plasma Tyr concentrations lower than controls (p = 0.019) but not significantly different from Tyr levels found in non-severe carriers (p = 0.197). (elsevier.com)
The dermis of all the relatives of PXE patients, established by haplotype analysis to be heterozygote carriers of a mutation in the PXE gene, exhibited several alterations very similar, although less severe, to those typical in PXE patients. (unimore.it)

Overdominance is a condition in genetics where the phenotype of the heterozygote lies outside of the phenotypical range of both homozygote parents, and heterozygous individuals have a higher fitness than homozygous individuals. (wikipedia.org)
Previous research, comparing measures of dominance, overdominance and epistasis (mostly in plants), found that the majority of cases of heterozygote advantage were due to complementation (or dominance), the masking of deleterious recessive alleles by wild-type alleles, as discussed in the articles Heterosis and Complementation (genetics), but there were also findings of overdominance, especially in rice. (wikipedia.org)
Specifically, those alleles , one found on each homologue , with Heterozygotes, are not identical to each other, either genotypically or, as is the case in practice with Mendelian genetics , phenotypically . (biologyaspoetry.com)

The fact that most patients with XPD mutations are compound heterozygotes complicates the understanding of genotype/phenotype relationships. (rupress.org)
Photoreceptor function in heterozygotes with insertion or deletion mutations in the RDS gene. (arvojournals.org)
CONCLUSIONS: Heterozygotes with these different peripherin/RDS gene mutations showed variation in clinical presentation but a similar pattern of receptor abnormalities. (arvojournals.org)
The effect of inbreeding on the distribution of compound heterozygotes: a lesson from Lipase H mutations in autosomal recessive woolly hair/hypotrichosis. (semanticscholar.org)
Overall, there was no increased risk for cancer among FA heterozygotes in this study of Fanconi relatives, although there is some evidence that FANCC mutations are possibly breast cancer susceptibility alleles. (elsevier.com)
Objective: Phosphatase and tensin homolog (PTEN) mutations are associated with human endometrial cancers, and PTEN heterozygote (±) mice have a high rate of endometrial neoplasia. (elsevier.com)
Phenylalanine hydroxylase mutations and phenylalanine-tyrosine metabolism in heterozygotes for phenylalanine hydroxylase deficiency. (elsevier.com)
CONCLUSION: Although the great heterogeneity of PAH mutations limits any general conclusion, the results suggest that monitoring plasma Tyr variations may be more sensitive than plasma Phe in assessing the severity of PAH mutations in HPA heterozygotes. (elsevier.com)
Impact of heterozygote CFTR mutations in COPD patients with chronic bronchitis. (cdc.gov)
Natural (directional) selection acting on overdominant mutations should drive them into the population but then, instead of bringing them to fixation, should maintain them as balanced polymorphisms via heterozygote advantage. (haldanessieve.org)
The fact that fitness overdominant mutations were always the first step in independent adaptive walks strongly supports the prediction that heterozygote advantage can arise as a common outcome of directional selection in diploids and demonstrates that overdominance of de novo adaptive mutations in diploids is not rare. (haldanessieve.org)

Initial genomic surveys have suggested that only a small proportion of loci have polymorphisms maintained by heterozygote advantage and this is consistent with the few examples generated from other approaches within given species. (nih.gov)
Common buzzards (Buteo buteo) show a plumage polymorphism that appears to be maintained by heterozygote advantage and allows a maladaptive form of mate choice to persist. (uni-bielefeld.de)
Krüger O, Lindström J, Amos W. Maladaptive mate choice maintained by heterozygote advantage. (uni-bielefeld.de)

In computer simulations, heterozygote excesses for 30 unlinked loci having various numbers of alleles and allele-frequency profiles were obtained for cohorts produced by samples of breeders drawn from an age-structured population and having known variance in reproductive success and effective number. (genetics.org)
2 , 6 , 14 In one study that included 9 Chuvash VHL R200W heterozygotes and 77 Chuvash participants with normal VHL alleles, the VHL R200W heterozygotes had significantly lower systemic blood pressures and higher serum PAI-1 concentrations. (haematologica.org)
heterozygote A diploid or polyploid individual that has different alleles forms of a given gene at at least one locus. (fungionline.org.uk)
This can happen by various mechanisms, in particular, when the heterozygotes for the alleles under consideration have a higher fitness than the homozygote . (wikipedia.org)
Heterozygote refers to the alleles that are present at single location ( locus ) on two homologues , that is, equivalent chromosomes as found within the same, diploid individual . (biologyaspoetry.com)
An organism is a heterozygote or is heterozygous at a locus or gene when it has different alleles occupying the gene's position in each of the homologous chromosomes. (askdefine.com)
In such cases, both alleles affect the phenotype of the heterozygote. (askdefine.com)
In our body, Heterozygote is an individual that as a genetic carrier has different alleles at one or more loci regarding a specific character. (wellnessadvocate.com)
A heterozygote is the result of the union of gametes of different genetic composition, each of which brings its own alleles to the zygote. (thefreedictionary.com)

Heterogeneity in the clastogenic response to x-rays in lymphocytes from Ataxia-telangiectasia heterozygotes and controls. (cdc.gov)
Identification of ataxia telangiectasia heterozygotes by flow cytometric analysis of X-ray damage. (semanticscholar.org)

A heterozygote advantage describes the case in which the heterozygous genotype has a higher relative fitness than either the homozygous dominant or homozygous recessive genotype. (wikipedia.org)
The hypothesis of overdominant selection (heterozygote advantage) at the MHC proposes that individuals heterozygous at HLA loci are able to present a greater variety of antigenic peptides than are homozygotes, resulting in a more productive immune response to a diverse array of pathogens ( 6 ). (sciencemag.org)
In heterozygote advantage , or heterotic balancing selection , an individual who is heterozygous at a particular gene locus has a greater fitness than a homozygous individual. (wikipedia.org)
In contrast to heterozygotes of XLHED, who frequently show mild involvement, heterozygous parents of patients with arHED show no features of the disorder. (biomedcentral.com)
In heterozygote advantage , an individual who is heterozygous at a particular gene locus has a greater fitness than a homozygous individual. (bionity.com)
A heterozygous genotype can have a higher relative fitness than either the homozygous dominant or homozygous recessive genotype - this is called a heterozygote advantage . (wikipedia.org)

A well-established case of heterozygote advantage is that of the gene involved in sickle cell anaemia. (wikipedia.org)
what is the level of gene expression in a homozygote and heterozygote? (madsci.org)
Subject: what is the level of gene expression in a homozygote and heterozygote? (madsci.org)
I would like to know about the level of gene expression in homozygote and heterozygote with respect to a transgenic loci and a wild type loci? (madsci.org)
I am under the impression that the level of gene expression in a homozygote and a heterozygote in the case of a dominant charcter is the same. (madsci.org)
Mutants with a heterozygote disadvantage, as it is known, reduce the evolutionary fitness of their carriers to varying degrees if they are only available to one gene copy (heterozygote) or exist in both gene copies (homozygote). (bio-medicine.org)
This demonstrates that the A-T gene predisposes heterozygotes to breast cancer. (nih.gov)
In addition, ≈70% of the heterozygotes died in utero , suggesting haploid insufficiency (i.e., one functional FAS gene is unable to support embryonic development efficiently). (pnas.org)
Heterozygote: An individual who has two different forms of a particular gene, one inherited from each parent. (fungionline.org.uk)
A heterozygote for cystic fibrosis CF has the CF gene on one chromosome 7 and the normal paired gene on the other chromosome 7. (fungionline.org.uk)
In Curacao, the HgbS allele has decreased in frequency over the past 300 years, and will eventually be lost from the gene pool due to heterozygote disadvantage. (wikipedia.org)
This usually happens when the heterozygote for a gene has a higher relative fitness than the homozygote . (wikipedia.org)
br)An analysis is made of single-gene ratios expected among trisomics in the progeny of interchange heterozygotes. (cnki.net)

Chylomicron-remnant clearance in homozygote and heterozygote Watanabe-heritable-hyperlipidaemic rabbits is defective. (portlandpress.com)
Note that typically the terms homozygote and heterozygote are used to describe the situation for one locus at a time. (biologyaspoetry.com)
What Is the Difference Between Homozygote and Heterozygote? (reference.com)

The evolution of overdominance: natural selection and heterozygote advantage. (ox.ac.uk)
Explain Natural Selection And Heterozygote Advantage is free HD wallpaper. (simple-natured.com)

A common example is the case where the heterozygote conveys both advantages and disadvantages, while both homozygotes convey a disadvantage. (wikipedia.org)
The homozygote wild type was perfectly healthy, but did not possess the improved viability of the heterozygote, and was thus at a disadvantage compared to the heterozygote in survival and reproduction. (wikipedia.org)
Mutants with heterozygote disadvantage can prevent spread of transgen. (bio-medicine.org)
A mutant with a heterozygote disadvantage can be maintained in a popul. (bio-medicine.org)
A mutant with a heterozygote disadvantage can be maintained in a population if it occurs frequently enough for sufficient homozygote offspring to be produced. (bio-medicine.org)
Populations containing mutants with heterozygote disadvantage develop into one of two stable states. (bio-medicine.org)
The researchers then analyzed computer-based simulations showing the effect of mutants with heterozygote disadvantage on two populations of equal size, which, as in nature, are subject to statistical fluctuations. (bio-medicine.org)
In contrast, mutants with heterozygote disadvantage can survive for many generations. (bio-medicine.org)
This is a homozygote disadvantage, or a heterozygote advantage. (whitherthewest.com)

Polymorphism can be maintained by selection favoring the heterozygote, and this mechanism is used to explain the occurrence of some kinds of genetic variability. (wikipedia.org)
For heterozygote advantage to be consequential i.e, to be capable of effectively stabilizing a balanced polymorphism against the stochastic fluctuations arising from random genetic drift, the fitness advantages of a heterozygote over its two homozygote have to be at least of order 1/ N 10. (fungionline.org.uk)
Such maladaptive behavior argues forcefully against mate choice based on "good genes," and its persistence is best explained by heterozygote advantage maintaining the polymorphism coupled with nongenetic mate choice based on sexual imprinting. (uni-bielefeld.de)
We found that polymorphism of rs1537514 showed the most significant effect: heterozygote associated with better clinical benefit (P = 0.002) and decreased risk of grade 3 or 4 gastrointestinal toxicity (P = 0.027), while the mutant homozygote associated with increased risk of severe gastrointestinal toxicity (P = 0.031) and thrombocytopenia (P = 009). (cdc.gov)

Mild anemia was present in 15% of VHL R200W heterozygotes and 34% of controls without a mutated VHL allele. (haematologica.org)
The present study was conducted to prospectively determine if heterozygotes for VHL R200W have discernable physiological and clinical differences from individuals without a mutated VHL allele, and if such differences exist, to consider whether they may represent a heterozygote advantage. (haematologica.org)
In a population with variation on both sex chromosomes, one does not know which sex chromosome carries a specific allele in a heterozygote of the heterogametic sex. (oxforddictionaries.com)
In the case of heterozygotes, one allele was randomly selected for each individual. (oxforddictionaries.com)
The individual tested was a heterozygote, necessarily possessing a copy of each allele. (oxforddictionaries.com)
[4] [5] Maintenance of the HgbS allele through positive selection is supported by significant evidence that heterozygotes have decreased fitness in regions where malaria is not prevalent. (wikipedia.org)
Assuming Rh+ is dominant allele D and Rh- is recessive d, calculate the expected number of Rh+ people who are heterozygotes. (cheapcustomwriters.com)
As one may be able to infer from the above idea, a heterozygote advantage is one in which it's more beneficial to have only one copy of an allele than two. (whitherthewest.com)
[3] The cell or organism is called a heterozygote specifically for the allele in question, and therefore, heterozygosity refers to a specific genotype. (wikipedia.org)
If the trait in question is determined by simple (complete) dominance, a heterozygote will express only the trait coded by the dominant allele, and the trait coded by the recessive allele will not be present. (wikipedia.org)

Such females are known as manifesting heterozygotes. (britannica.com)
affect females who are "manifesting heterozygotes" ( see the section Inheritance), presenting with severe disease during infancy or later in life during times of metabolic stress-for instance, during viral illness or childbirth. (britannica.com)

The specific case of heterozygote advantage due to a single locus is known as overdominance. (wikipedia.org)
Second, the heterozygote advantage arises because of the super-position of two opposite directional selection pressures malaria and sickle-cell anaemia, so it is not really a true case of heterozygote advantage arising from the heterozygote having superior fitness for a specific trait. (fungionline.org.uk)
A well-studied case of heterozygote advantage is that of sickle cell anemia . (bionity.com)

Unless further studies provide large numbers of loci with heterozygote advantage, it appears that loci with heterozygote advantage must be considered only a small minority of all loci in a species. (nih.gov)
This is not to say that some heterozygote advantage loci do not have important adaptive functions, but that their role in overall evolutionary change might be more of an unusual phenomenon than a major player in adaptation. (nih.gov)
An excess of heterozygotes (in five out of the eight loci genotyped) was found, which suggests a positive selection mechanism for heterozygotes. (csic.es)
Heterozygote superiority is rare see Hedrick 2012 Trends Ecol Evol 2712: 698-704, and many examples that are assumed to be heterozygote superiority, such as MHC loci, can be explained by heterozygote advantage through dominance Penn et al. (fungionline.org.uk)

Both of these concepts imply that heterozygotes and/or hybrids have a phenotype that lies outside of the range described by the homozygotes (or, for heterosis, either parent or parent population). (stackexchange.com)
In particular, the phenomenon known as overdominance occurs when a heterozygote has a more extreme phenotype than that of either of its parents. (stackexchange.com)
Collectively, these findings suggest that Vmat2 heterozygotes display a depressive-like phenotype that is devoid of anxiety-like behavior. (jneurosci.org)
Given the effects of reserpine on depressive-like symptoms in humans ( Freis, 1954 ), we examined whether Vmat2 heterozygotes would display a similar phenotype. (jneurosci.org)

The heterozygotes of exon polymorphisms (rs1801131, rs1801133) also yielded better clinical benefit (P = 0.030 for rs1801131) and decreased risk of severe gastrointestinal toxicity (P = 0.004 for rs1801131) or thrombocytopenia (P = 0.016 for 1801133). (cdc.gov)
However, overall survival (OS) and progression-free survival (PFS) did not differ for the MTHFR polymorphisms, except for heterozygote of rs1537514 showing significant effects with better PFS (P = 0.022). (cdc.gov)

Page T., Bakay B., Nyhan W.L. (1984) Detection of Hypoxanthine Guanine Phosphoribosyl Transferase Heterozygotes by Thin Layer Chromatography and Autoradiography. (springer.com)
Radioimmunoassay and heat denaturation enzyme assay for the detection of Tay-sachs heterozygotes during pregnancy. (biomedsearch.com)
Heterozygote detection in angiokeratoma corporis diffusum (Anderson-Fabry disease). (bmj.com)
Detection of heterozygotes in both parents of homozygous patients with Von Willebrand's disease. (bmj.com)
Heterozygote Detection" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings) . (childrensmercy.org)
This graph shows the total number of publications written about "Heterozygote Detection" by people in this website by year, and whether "Heterozygote Detection" was a major or minor topic of these publications. (childrensmercy.org)
Below are the most recent publications written about "Heterozygote Detection" by people in Profiles. (childrensmercy.org)
Detection of CAH heterozygotes. (elsevier.com)

Homozygotes and heterozygotes at individual sites were distinguished by their chromatographic patterns. (oxforddictionaries.com)
This paper describes a Bidirectional PASA (Bi-PASA) method, which was developed to distinguish between homozygotes and heterozygotes in one PCR reaction. (diva-portal.org)

Simulation experiments were used to show the impact of varying extraction efficiency, aliquot proportion, and PCR efficiency on the heterozygote balance of a range of diploid and haploid cells. (uio.no)

Immature hepatic function is one explanation for neonatal transient galactosuria, but heterozygotes or the carriers of galactose degradation enzyme deficiencies were also suspected in some of the newborns, judging from the comparisons of urinary galactose and 4HPLA excretion between neonates and patients with galactosemia. (nii.ac.jp)
However, these heterozygote individuals, known as carriers of the sickle cell trait , may suffer problems from time to time. (wikipedia.org)
For this purpose, the levels of remnant cholesterol and LDL-c were determined in APOC3 LOF heterozygotes versus non-carriers, by means of a meta-analysis of 8 study cohorts including 137,895 individuals. (pace-cme.org)
Moreover, LDL-c levels of APOC3 LOF heterozygotes were compared with those of non-carriers in 75,725 individuals in the two prospective Danish general population cohorts (Copenhagen City Heart Study and Copenhagen General Population Study), and it was assessed whether lipid-lowering therapy masked the associations of LDL cholesterol with IVD. (pace-cme.org)
APOC3 LOF heterozygotes had 4% (95%CI: 1%-6%) lower levels of LDL-c compared with non-carriers in a fixed effects model and 5% (95%CI: 1%-8%) lower levels of LDL-c in a random effects model. (pace-cme.org)
In the general population, remnant cholesterol was 44% (0.3 mmol/L) lower (P=1×10−51), and LDL-c was 3% (0.1 mmol/L) lower (P=0.06) in APO3 LOF heterozygotes versus non-carriers overall, regardless of lipid-lowering therapy. (pace-cme.org)
After correcting for lipid-lowering therapy, LOF heterozygotes in the general population had 43% (0.3 mmol/L) lower levels of remnant cholesterol (P=5×10−49) and 4% (0.1 mmol/L) lower levels of LDL-c (P=0.008) compared with non-carriers. (pace-cme.org)
When excluding participants on lipid-lowering therapy at the time of lipid assessment, remnant cholesterol was 44% (0.3 mmol/L) lower (P=2×10−49), and LDL-c was 3% (0.1 mmol/L) lower (P=0.02) in LOF heterozygotes compared with non-carriers. (pace-cme.org)
The mediation analysis showed that the lower levels of remnant cholesterol in LOF heterozygotes versus non-carriers mediated 37% of the lower IVD risk (P value for the indirect effect, P=6×10−37) and 54% of the lower IHD risk (P value for the indirect effect, P=1×10−37), whereas the 4% lower levels of LDL-c mediated only 1% and 2% of the lower risks. (pace-cme.org)
The lower IVD risk in APOC3 LOF heterozygotes compared with non-carriers is largely due to the significantly lower levels of remnant cholesterol and not due to lower levels of LDL-c, and this observation was not affected by lipid-lowering therapy. (pace-cme.org)

Flow cytometry was used to identify heterozygotes for the autosomal recessive DNA-repair deficiency disease ataxia telangiectasia (AT). (semanticscholar.org)

The first experimental confirmation of heterozygote advantage was with Drosophila melanogaster, a fruit fly that has been a model organism for genetic research. (wikipedia.org)

[3] Due to unexpected high frequencies of heterozygotes, and an elevated level of heterozygote fitness, heterozygotic advantage may also be called "overdominance" in some literature. (wikipedia.org)
However, I think you are looking for the terms Overdominance (also called Heterozygote advantage ) and Heterosis (also Hybrid vigor ). (stackexchange.com)
Indeed, in a few examples, a trait that shows overdominance sometimes confers a survival advantage in the heterozygote (Parsons & Bodmer, 1961). (stackexchange.com)

We show that prolonged mTert heterozygosity (for greater than ten generations) did not elicit disease, even upon heterozygote interbreeding, and that telomeres reset to wild-type lengths. (biologists.org)

More recent research, however, has established that there is also an epigenetic contribution to heterozygote advantage, primarily as determined in plants, though also reported in mice. (wikipedia.org)
When Fasn +/- heterozygotes were interbred, Fasn -/- null mutant mice died at the preimplantation stage. (pnas.org)

An estimate based on heterozygote excess might have certain advantages over the previous estimates, requiring only single-locus and single-cohort data, but the sampling error among individuals and the effect of departures from random union of gametes still need-to be explored. (genetics.org)

Vmat2 homozygous mutants [knock-outs (KOs)] die soon after birth, whereas heterozygotes survive with normal growth, feeding, and reproductive behaviors. (jneurosci.org)

Impact of iron deficiency on hemoglobin A2% in obligate β-thalassemia heterozygotes. (sigmaaldrich.com)

Heterozygote Definition of Heterozygote by Merriam-Webster. (fungionline.org.uk)
Post the Definition of heterozygote to Facebook Share the Definition of heterozygote on Twitter Time Traveler for heterozygote. (fungionline.org.uk)
Definition of Heterozygote. (fungionline.org.uk)

Summary(#br)In Pisum sativum tertiary trisomics and trisomic interchange heterozygotes have been derived from Hammarlund's K -line interchange heterozygote, which has a meiotic association of four chromosomes. (cnki.net)

Confluent G0/G1 fibroblasts from 4 homozygotes (at/at), 5 obligate heterozygotes (at/+) and 7 presumed normal controls (+/+) were X-irradiated with 200 Rad and subcultured immediately in medium containing 5-bromodeoxyuridine (BrdU). (semanticscholar.org)

Thus, even complex aberration heterozygotes usually allow high frequencies of meiotic pairing, synapsis, and double-strand break formation in Drosophila oocytes. (ku.edu)

It is in this way that natural selection preserves stable frequencies of both the heterozygote and the homozygote dominant phenotypes. (bionity.com)

About 60-70 % of the heterozygotes of X-linked hypohidrotic ectodermal dysplasia (XLHED) show some clinical manifestations of the disease. (biomedcentral.com)

How many of these genes are undergoing heterozygote advantage selection is only beginning to be known. (nih.gov)

Being Well-Born Michael F. In this character, then, dominance almost always fails to show itself in the heterozygote and often fails in pure dominants. (fungionline.org.uk)

Ms. Parrott teaches about the concept of heterozygote advantage using the example of sickle cell anemia. (mobilehealthdata.com)

Heterozygote advantage as a natural consequence of adaptation in diploids PNAS. (fungionline.org.uk)

Simulations suggest that pristine diluted DNA is an acceptable approximation in validations to infer heterozygote balance. (uio.no)

Auerbach, Arleen D. / Genetic heterogeneity among fanconi anemia heterozygotes and risk of cancer . (elsevier.com)

Heterozygote advantage is a major underlying mechanism for heterosis, or "hybrid vigor", which is the improved or increased function of any biological quality in a hybrid offspring. (wikipedia.org)

Heterozygotes were examined clinically and with rod and cone perimetry, dark adaptometry, and rod- and cone-isolated electroretinograms (ERGs). (arvojournals.org)

The two major and most studied are heterozygote advantage and frequency-dependent selection. (wikipedia.org)

Examples from the Web for heterozygote. (fungionline.org.uk)

Such mosaicism has been demonstrated in populations of cultured fibroblasts and in hair root follicles of heterozygotes (4,5). (springer.com)
The relatively high rates of asexual reproduction may be the result of adaptation to the environmental stability, while heterozygote selection would help maintain some genetic diversity in the populations. (csic.es)
For example, in inbred populations there may be very few heterozygotes but several different homozygotes. (oxforddictionaries.com)

Homozygote (left) versus heterozygote (right). (biologyaspoetry.com)

Fertility in balanced heterozygotes for a familial centric fusion translocation, t(DgDg). (bmj.com)

Search for Heterozygote advantage in other articles. (academickids.com)

The heterozygote has a permanent advantage (a higher fitness) wherever malaria exists. (wikipedia.org)
This resistance is favored by natural selection in tropical regions where malaria (a common and deadly sickness caused by the protozoan parasite Plasmodium falciparum ) is present and so the heterozygote has an evolutionary edge. (bionity.com)

The predicted prevalence of increased sensitivity to X-rays in controls is approximately three- to 30-fold greater than the estimated frequency of A-T heterozygotes in the general population. (cdc.gov)
To investigate the prevalence of bleeding in heterozygotes for prothrombin deficiencies. (ovid.com)

The hypothesis that A-T heterozygotes are predisposed to breast cancer was tested by the unbiased statistically powerful index-test method based on molecular genotyping. (nih.gov)

Do the 4-toed heterozygotes produce a larger proportion of imperfect dominants in F2 than the 5-toed heterozygotes ? (dictionary.com)

In twenty healthy Icelandic heterozygotes for WD and their age- and gender-matched controls, copper concentration in plasma, ceruloplasmin (CP) concentration, CP oxidative activity and CP-specific oxidative activity in serum and superoxide dismutase (SOD1) activity in erythrocytes were determined. (dovepress.com)
During pregnancy an intermediate isoenzyme (HEX I) increases in activity in serum and obscures the heterozygote status. (biomedsearch.com)

Anatomy11

Organisms8

Diseases57

Chemicals and Drugs45

Analytical, Diagnostic and Therapeutic Techniques and Equipment25

Phenomena and Processes59

Disciplines and Occupations1

Information Science3

Named Groups5

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Geographicals2

Mapping of the homothallic genes, HM alpha and HMa, in Saccharomyces yeasts. (1/10346)

The Drosophila kismet gene is related to chromatin-remodeling factors and is required for both segmentation and segment identity. (2/10346)

Mrj encodes a DnaJ-related co-chaperone that is essential for murine placental development. (3/10346)

Identification of sonic hedgehog as a candidate gene responsible for the polydactylous mouse mutant Sasquatch. (4/10346)

Factor VII deficiency rescues the intrauterine lethality in mice associated with a tissue factor pathway inhibitor deficit. (5/10346)

Loss-of-function mutations in the rice homeobox gene OSH15 affect the architecture of internodes resulting in dwarf plants. (6/10346)

Thyroid hormone effects on Krox-24 transcription in the post-natal mouse brain are developmentally regulated but are not correlated with mitosis. (7/10346)

Angiotensinogen gene polymorphisms M235T/T174M: no excess transmission to hypertensive Chinese. (8/10346)

Heterozygote

Heterozygote Detection

Homozygote

Alleles

Genotype

Mutation

Pedigree

Phenotype

Polymorphism, Genetic

Gene Frequency

Thalassemia

Genes, Recessive

Hyperlipoproteinemia Type I

Hemoglobin A2

Genetic Variation

Genes, Dominant

DNA Mutational Analysis

Genes, Lethal

Crosses, Genetic

Base Sequence

Hemoglobins, Abnormal

Hemochromatosis

Polymerase Chain Reaction

Ataxia Telangiectasia

Genetic Predisposition to Disease

Point Mutation

Haplotypes

Hyperlipoproteinemia Type II

Mutation, Missense

Molecular Sequence Data

Cystinuria

Hypobetalipoproteinemias

Tay-Sachs Disease

Exons

Hemoglobin E

Jews

Adenine Phosphoribosyltransferase

Genetic Linkage

Mice, Mutant Strains

Models, Genetic

Fetal Hemoglobin

alpha-Thalassemia

Genetic Testing

Polymorphism, Single Nucleotide

Hemoglobinopathies

Chromosome Mapping

Inbreeding

Genetics, Population

Shrews

Mice, Knockout

Sandhoff Disease

Polymorphism, Restriction Fragment Length

beta-Thalassemia

Glucosephosphate Dehydrogenase Deficiency

DNA

Genetic Markers

Amino Acid Metabolism, Inborn Errors

Phenylketonurias

Microsatellite Repeats

Globins

Frameshift Mutation

Selection, Genetic

Lipid Metabolism, Inborn Errors

Case-Control Studies

Metabolism, Inborn Errors

Codon, Nonsense

Fabry Disease

Hypolipoproteinemias

Consanguinity

Hybrid Vigor

Hexosaminidase A

Gene Deletion

Homocystinuria

Mice, Inbred C57BL

Lipidoses

Lecithin Acyltransferase Deficiency

Cystic Fibrosis

Apolipoproteins B

Crossing Over, Genetic

Electrophoresis, Starch Gel