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Genetic Diseases, Inborn: Diseases that are caused by genetic mutations present during embryo or fetal development, although they may be observed later in life. The mutations may be inherited from a parent's genome or they may be acquired in utero.Mutation: 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.Eugenics: The attempt to improve the PHENOTYPES of future generations of the human population by fostering the reproduction of those with favorable phenotypes and GENOTYPES and hampering or preventing BREEDING by those with "undesirable" phenotypes and genotypes. The concept is largely discredited. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)Genetics, Medical: A subdiscipline of human genetics which entails the reliable prediction of certain human disorders as a function of the lineage and/or genetic makeup of an individual or of any two parents or potential parents.Genetic Diseases, Y-Linked: Genetic diseases that are linked to mutant ALLELES on the Y CHROMOSOME in humans (Y CHROMOSOME, HUMAN) or the Y chromosome in other species. Included here are animal models of human Y-linked diseases.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Rare Diseases: A large group of diseases which are characterized by a low prevalence in the population. They frequently are associated with problems in diagnosis and treatment.Molecular Sequence Data: 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.Genome, Human: The complete genetic complement contained in the DNA of a set of CHROMOSOMES in a HUMAN. The length of the human genome is about 3 billion base pairs.Cystic Fibrosis: 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.Heart Septal Defects, Ventricular: Developmental abnormalities in any portion of the VENTRICULAR SEPTUM resulting in abnormal communications between the two lower chambers of the heart. Classification of ventricular septal defects is based on location of the communication, such as perimembranous, inlet, outlet (infundibular), central muscular, marginal muscular, or apical muscular defect.Genetic Diseases, X-Linked: Genetic diseases that are linked to gene mutations on the X CHROMOSOME in humans (X CHROMOSOME, HUMAN) or the X CHROMOSOME in other species. Included here are animal models of human X-linked diseases.Genetic Testing: 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.Cystic Fibrosis Transmembrane Conductance Regulator: 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)Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Disease: A definite pathologic process with a characteristic set of signs and symptoms. It may affect the whole body or any of its parts, and its etiology, pathology, and prognosis may be known or unknown.Genetic Counseling: An educational process that provides information and advice to individuals or families about a genetic condition that may affect them. The purpose is to help individuals make informed decisions about marriage, reproduction, and other health management issues based on information about the genetic disease, the available diagnostic tests, and management programs. Psychosocial support is usually offered.Heart Defects, Congenital: Developmental abnormalities involving structures of the heart. These defects are present at birth but may be discovered later in life.Models, Genetic: 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.Genetic Therapy: Techniques and strategies which include the use of coding sequences and other conventional or radical means to transform or modify cells for the purpose of treating or reversing disease conditions.Metabolism, Inborn Errors: Errors in metabolic processes resulting from inborn genetic mutations that are inherited or acquired in utero.Heart Septal Defects, Atrial: Developmental abnormalities in any portion of the ATRIAL SEPTUM resulting in abnormal communications between the two upper chambers of the heart. Classification of atrial septal defects is based on location of the communication and types of incomplete fusion of atrial septa with the ENDOCARDIAL CUSHIONS in the fetal heart. They include ostium primum, ostium secundum, sinus venosus, and coronary sinus defects.Codon, Nonsense: 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.Pedigree: 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.Chromosome Mapping: Any method used for determining the location of and relative distances between genes on a chromosome.Alleles: Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.Judaism: The religion of the Jews characterized by belief in one God and in the mission of the Jews to teach the Fatherhood of God as revealed in the Hebrew Scriptures. (Webster, 3d ed)Prenatal Diagnosis: Determination of the nature of a pathological condition or disease in the postimplantation EMBRYO; FETUS; or pregnant female before birth.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Genes, Recessive: Genes that influence the PHENOTYPE only in the homozygous state.Genetic Predisposition to Disease: A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.Congenital Abnormalities: Malformations of organs or body parts during development in utero.DNA Mutational Analysis: Biochemical identification of mutational changes in a nucleotide sequence.Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.DNA: 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).Probability Theory: The branch of mathematics dealing with the purely logical properties of probability. Its theorems underlie most statistical methods. (Last, A Dictionary of Epidemiology, 2d ed)Molecular Biology: A discipline concerned with studying biological phenomena in terms of the chemical and physical interactions of molecules.Human Genome Project: A coordinated effort of researchers to map (CHROMOSOME MAPPING) and sequence (SEQUENCE ANALYSIS, DNA) the human GENOME.Polymerase Chain Reaction: 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.Sphingolipidoses: A group of inherited metabolic disorders characterized by the intralysosomal accumulation of SPHINGOLIPIDS primarily in the CENTRAL NERVOUS SYSTEM and to a variable degree in the visceral organs. They are classified by the enzyme defect in the degradation pathway and the substrate accumulation (or storage). Clinical features vary in subtypes but neurodegeneration is a common sign.Nonsense Mediated mRNA Decay: An mRNA metabolic process that distinguishes a normal STOP CODON from a premature stop codon (NONSENSE CODON) and facilitates rapid degradation of aberrant mRNAs containing premature stop codons.Heterozygote: An individual having different alleles at one or more loci regarding a specific character.Fanconi Anemia: Congenital disorder affecting all bone marrow elements, resulting in ANEMIA; LEUKOPENIA; and THROMBOPENIA, and associated with cardiac, renal, and limb malformations as well as dermal pigmentary changes. Spontaneous CHROMOSOME BREAKAGE is a feature of this disease along with predisposition to LEUKEMIA. There are at least 7 complementation groups in Fanconi anemia: FANCA, FANCB, FANCC, FANCD1, FANCD2, FANCE, FANCF, FANCG, and FANCL. (from Online Mendelian Inheritance in Man, http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=227650, August 20, 2004)Targeted Gene Repair: A technique which uses synthetic oligonucleotides to direct the cell's inherent DNA repair system to correct a mutation at a specific site in an episome or chromosome.Syndrome: A characteristic symptom complex.Exons: 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.Mice, Knockout: 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.Genetic Vectors: DNA molecules capable of autonomous replication within a host cell and into which other DNA sequences can be inserted and thus amplified. Many are derived from PLASMIDS; BACTERIOPHAGES; or VIRUSES. They are used for transporting foreign genes into recipient cells. Genetic vectors possess a functional replicator site and contain GENETIC MARKERS to facilitate their selective recognition.Heart Septal Defects: Abnormalities in any part of the HEART SEPTUM resulting in abnormal communication between the left and the right chambers of the heart. The abnormal blood flow inside the heart may be caused by defects in the ATRIAL SEPTUM, the VENTRICULAR SEPTUM, or both.Mutation, Missense: 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)Amino Acid Sequence: 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.Genetic Techniques: Chromosomal, biochemical, intracellular, and other methods used in the study of genetics.Chromosome Disorders: Clinical conditions caused by an abnormal chromosome constitution in which there is extra or missing chromosome material (either a whole chromosome or a chromosome segment). (from Thompson et al., Genetics in Medicine, 5th ed, p429)Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Genetic Linkage: The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.Point Mutation: 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.Abnormalities, MultipleHeterozygote Detection: Identification of genetic carriers for a given trait.Gene Targeting: 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.Gene Deletion: 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.Homozygote: An individual in which both alleles at a given locus are identical.Gene Transfer Techniques: The introduction of functional (usually cloned) GENES into cells. A variety of techniques and naturally occurring processes are used for the gene transfer such as cell hybridization, LIPOSOMES or microcell-mediated gene transfer, ELECTROPORATION, chromosome-mediated gene transfer, TRANSFECTION, and GENETIC TRANSDUCTION. Gene transfer may result in genetically transformed cells and individual organisms.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Tay-Sachs Disease: 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.Preimplantation Diagnosis: Determination of the nature of a pathological condition or disease in the OVUM; ZYGOTE; or BLASTOCYST prior to implantation. CYTOGENETIC ANALYSIS is performed to determine the presence or absence of genetic disease.Polymorphism, Single Nucleotide: A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.Muscular Dystrophy, Duchenne: An X-linked recessive muscle disease caused by an inability to synthesize DYSTROPHIN, which is involved with maintaining the integrity of the sarcolemma. Muscle fibers undergo a process that features degeneration and regeneration. Clinical manifestations include proximal weakness in the first few years of life, pseudohypertrophy, cardiomyopathy (see MYOCARDIAL DISEASES), and an increased incidence of impaired mentation. Becker muscular dystrophy is a closely related condition featuring a later onset of disease (usually adolescence) and a slowly progressive course. (Adams et al., Principles of Neurology, 6th ed, p1415)Models, Biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.Genetic Markers: A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.Tuberous Sclerosis: Autosomal dominant neurocutaneous syndrome classically characterized by MENTAL RETARDATION; EPILEPSY; and skin lesions (e.g., adenoma sebaceum and hypomelanotic macules). There is, however, considerable heterogeneity in the neurologic manifestations. It is also associated with cortical tuber and HAMARTOMAS formation throughout the body, especially the heart, kidneys, and eyes. Mutations in two loci TSC1 and TSC2 that encode hamartin and tuberin, respectively, are associated with the disease.Membrane Proteins: 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.Mitochondrial Diseases: Diseases caused by abnormal function of the MITOCHONDRIA. They may be caused by mutations, acquired or inherited, in mitochondrial DNA or in nuclear genes that code for mitochondrial components. They may also be the result of acquired mitochondria dysfunction due to adverse effects of drugs, infections, or other environmental causes.Trinucleotide Repeats: Microsatellite repeats consisting of three nucleotides dispersed in the euchromatic arms of chromosomes.Dysautonomia, Familial: An autosomal disorder of the peripheral and autonomic nervous systems limited to individuals of Ashkenazic Jewish descent. Clinical manifestations are present at birth and include diminished lacrimation, defective thermoregulation, orthostatic hypotension (HYPOTENSION, ORTHOSTATIC), fixed pupils, excessive SWEATING, loss of pain and temperature sensation, and absent reflexes. Pathologic features include reduced numbers of small diameter peripheral nerve fibers and autonomic ganglion neurons. (From Adams et al., Principles of Neurology, 6th ed, p1348; Nat Genet 1993;4(2):160-4)Factor IX: Storage-stable blood coagulation factor acting in the intrinsic pathway. Its activated form, IXa, forms a complex with factor VIII and calcium on platelet factor 3 to activate factor X to Xa. Deficiency of factor IX results in HEMOPHILIA B (Christmas Disease).Homocystinuria: 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)Chromosome Aberrations: Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Genes, Dominant: Genes that influence the PHENOTYPE both in the homozygous and the heterozygous state.Genetic Variation: Genotypic differences observed among individuals in a population.Exome: That part of the genome that corresponds to the complete complement of EXONS of an organism or cell.Lipid Metabolism Disorders: Pathological conditions resulting from abnormal anabolism or catabolism of lipids in the body.Hemochromatosis: 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)Haploinsufficiency: A copy number variation that results in reduced GENE DOSAGE due to any loss-of-function mutation. The loss of heterozygosity is associated with abnormal phenotypes or diseased states because the remaining gene is insufficient.Hemophilia B: A deficiency of blood coagulation factor IX inherited as an X-linked disorder. (Also known as Christmas Disease, after the first patient studied in detail, not the holy day.) Historical and clinical features resemble those in classic hemophilia (HEMOPHILIA A), but patients present with fewer symptoms. Severity of bleeding is usually similar in members of a single family. Many patients are asymptomatic until the hemostatic system is stressed by surgery or trauma. Treatment is similar to that for hemophilia A. (From Cecil Textbook of Medicine, 19th ed, p1008)Chromosomes, Human: Very long DNA molecules and associated proteins, HISTONES, and non-histone chromosomal proteins (CHROMOSOMAL PROTEINS, NON-HISTONE). Normally 46 chromosomes, including two sex chromosomes are found in the nucleus of human cells. They carry the hereditary information of the individual.Dystrophin: A muscle protein localized in surface membranes which is the product of the Duchenne/Becker muscular dystrophy gene. Individuals with Duchenne muscular dystrophy usually lack dystrophin completely while those with Becker muscular dystrophy have dystrophin of an altered size. It shares features with other cytoskeletal proteins such as SPECTRIN and alpha-actinin but the precise function of dystrophin is not clear. One possible role might be to preserve the integrity and alignment of the plasma membrane to the myofibrils during muscle contraction and relaxation. MW 400 kDa.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Sequence Analysis, DNA: A multistage process that includes cloning, physical mapping, subcloning, determination of the DNA SEQUENCE, and information analysis.Consanguinity: The magnitude of INBREEDING in humans.beta-Thalassemia: 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.Mice, Inbred C57BLDependovirus: A genus of the family PARVOVIRIDAE, subfamily PARVOVIRINAE, which are dependent on a coinfection with helper adenoviruses or herpesviruses for their efficient replication. The type species is Adeno-associated virus 2.Infant, Newborn: An infant during the first month after birth.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.DNA Repair: The reconstruction of a continuous two-stranded DNA molecule without mismatch from a molecule which contained damaged regions. The major repair mechanisms are excision repair, in which defective regions in one strand are excised and resynthesized using the complementary base pairing information in the intact strand; photoreactivation repair, in which the lethal and mutagenic effects of ultraviolet light are eliminated; and post-replication repair, in which the primary lesions are not repaired, but the gaps in one daughter duplex are filled in by incorporation of portions of the other (undamaged) daughter duplex. Excision repair and post-replication repair are sometimes referred to as "dark repair" because they do not require light.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Penetrance: 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)Muscular Dystrophies: A heterogeneous group of inherited MYOPATHIES, characterized by wasting and weakness of the SKELETAL MUSCLE. They are categorized by the sites of MUSCLE WEAKNESS; AGE OF ONSET; and INHERITANCE PATTERNS.Phenylketonurias: 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).Cells, Cultured: 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.Databases, Genetic: Databases devoted to knowledge about specific genes and gene products.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.alpha 1-Antitrypsin Deficiency: Deficiency of the protease inhibitor ALPHA 1-ANTITRYPSIN that manifests primarily as PULMONARY EMPHYSEMA and LIVER CIRRHOSIS.Proteins: Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.Zebrafish: An exotic species of the family CYPRINIDAE, originally from Asia, that has been introduced in North America. They are used in embryological studies and to study the effects of certain chemicals on development.Kartagener Syndrome: An autosomal recessive disorder characterized by a triad of DEXTROCARDIA; INFERTILITY; and SINUSITIS. The syndrome is caused by mutations of DYNEIN genes encoding motility proteins which are components of sperm tails, and CILIA in the respiratory and the reproductive tracts.RNA, Messenger: 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.Gene Expression Regulation, Developmental: 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.Steroid 21-Hydroxylase: An adrenal microsomal cytochrome P450 enzyme that catalyzes the 21-hydroxylation of steroids in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP21 gene, converts progesterones to precursors of adrenal steroid hormones (CORTICOSTERONE; HYDROCORTISONE). Defects in CYP21 cause congenital adrenal hyperplasia (ADRENAL HYPERPLASIA, CONGENITAL).Recombination, Genetic: 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.DNA Primers: 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.Polycystic Kidney Diseases: Hereditary diseases that are characterized by the progressive expansion of a large number of tightly packed CYSTS within the KIDNEYS. They include diseases with autosomal dominant and autosomal recessive inheritance.Gene Frequency: The proportion of one particular in the total of all ALLELES for one genetic locus in a breeding POPULATION.Computational Biology: A field of biology concerned with the development of techniques for the collection and manipulation of biological data, and the use of such data to make biological discoveries or predictions. This field encompasses all computational methods and theories for solving biological problems including manipulation of models and datasets.Transcription Factors: Endogenous substances, usually proteins, which are effective in the initiation, stimulation, or termination of the genetic transcription process.Alu Elements: The Alu sequence family (named for the restriction endonuclease cleavage enzyme Alu I) is the most highly repeated interspersed repeat element in humans (over a million copies). It is derived from the 7SL RNA component of the SIGNAL RECOGNITION PARTICLE and contains an RNA polymerase III promoter. Transposition of this element into coding and regulatory regions of genes is responsible for many heritable diseases.Mucopolysaccharidosis I: Systemic lysosomal storage disease caused by a deficiency of alpha-L-iduronidase (IDURONIDASE) and characterized by progressive physical deterioration with urinary excretion of DERMATAN SULFATE and HEPARAN SULFATE. There are three recognized phenotypes representing a spectrum of clinical severity from severe to mild: Hurler syndrome, Hurler-Scheie syndrome and Scheie syndrome (formerly mucopolysaccharidosis V). Symptoms may include DWARFISM; hepatosplenomegaly; thick, coarse facial features with low nasal bridge; corneal clouding; cardiac complications; and noisy breathing.Sequence Deletion: Deletion of sequences of nucleic acids from the genetic material of an individual.Ataxia Telangiectasia: 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).Genome: The genetic complement of an organism, including all of its GENES, as represented in its DNA, or in some cases, its RNA.Saccharomyces cerevisiae: A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.Kallmann Syndrome: A genetically heterogeneous disorder caused by hypothalamic GNRH deficiency and OLFACTORY NERVE defects. It is characterized by congenital HYPOGONADOTROPIC HYPOGONADISM and ANOSMIA, possibly with additional midline defects. It can be transmitted as an X-linked (GENETIC DISEASES, X-LINKED), an autosomal dominant, or an autosomal recessive trait.Fibroblasts: Connective tissue cells which secrete an extracellular matrix rich in collagen and other macromolecules.Muscular Atrophy, Spinal: A group of disorders marked by progressive degeneration of motor neurons in the spinal cord resulting in weakness and muscular atrophy, usually without evidence of injury to the corticospinal tracts. Diseases in this category include Werdnig-Hoffmann disease and later onset SPINAL MUSCULAR ATROPHIES OF CHILDHOOD, most of which are hereditary. (Adams et al., Principles of Neurology, 6th ed, p1089)Gene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.Neoplasms: New abnormal growth of tissue. Malignant neoplasms show a greater degree of anaplasia and have the properties of invasion and metastasis, compared to benign neoplasms.RNA Splicing: The ultimate exclusion of nonsense sequences or intervening sequences (introns) before the final RNA transcript is sent to the cytoplasm.TRPP Cation Channels: A subgroup of TRP cation channels that are widely expressed in various cell types. Defects are associated with POLYCYSTIC KIDNEY DISEASES.Codon, Terminator: Any codon that signals the termination of genetic translation (TRANSLATION, GENETIC). PEPTIDE TERMINATION FACTORS bind to the stop codon and trigger the hydrolysis of the aminoacyl bond connecting the completed polypeptide to the tRNA. Terminator codons do not specify amino acids.Mice, Inbred CFTR: A strain of mice widely studied as a model for cystic fibrosis. These mice are generated from embryonic stem cells in which the CFTR (cystic fibrosis transmembrane conductance regulator) gene is inactivated by gene targeting. As a result, all mice have one copy of this altered gene in all their tissues. Mice homozygous for the disrupted gene exhibit many features common to young cystic fibrosis patients, including failure to thrive, meconium ileus, and alteration of mucous and serous glands.Hemophilia A: The classic hemophilia resulting from a deficiency of factor VIII. It is an inherited disorder of blood coagulation characterized by a permanent tendency to hemorrhage.Ethylnitrosourea: A nitrosourea compound with alkylating, carcinogenic, and mutagenic properties.Polycystic Kidney, Autosomal Dominant: Kidney disorders with autosomal dominant inheritance and characterized by multiple CYSTS in both KIDNEYS with progressive deterioration of renal function.Intellectual Disability: Subnormal intellectual functioning which originates during the developmental period. This has multiple potential etiologies, including genetic defects and perinatal insults. Intelligence quotient (IQ) scores are commonly used to determine whether an individual has an intellectual disability. IQ scores between 70 and 79 are in the borderline range. Scores below 67 are in the disabled range. (from Joynt, Clinical Neurology, 1992, Ch55, p28)Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Survival of Motor Neuron 1 Protein: A SMN complex protein that is essential for the function of the SMN protein complex. In humans the protein is encoded by a single gene found near the inversion telomere of a large inverted region of CHROMOSOME 5. Mutations in the gene coding for survival of motor neuron 1 protein may result in SPINAL MUSCULAR ATROPHIES OF CHILDHOOD.Down Syndrome: A chromosome disorder associated either with an extra chromosome 21 or an effective trisomy for chromosome 21. Clinical manifestations include hypotonia, short stature, brachycephaly, upslanting palpebral fissures, epicanthus, Brushfield spots on the iris, protruding tongue, small ears, short, broad hands, fifth finger clinodactyly, Simian crease, and moderate to severe INTELLECTUAL DISABILITY. Cardiac and gastrointestinal malformations, a marked increase in the incidence of LEUKEMIA, and the early onset of ALZHEIMER DISEASE are also associated with this condition. Pathologic features include the development of NEUROFIBRILLARY TANGLES in neurons and the deposition of AMYLOID BETA-PROTEIN, similar to the pathology of ALZHEIMER DISEASE. (Menkes, Textbook of Child Neurology, 5th ed, p213)Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Nuclear Proteins: Proteins found in the nucleus of a cell. Do not confuse with NUCLEOPROTEINS which are proteins conjugated with nucleic acids, that are not necessarily present in the nucleus.Founder Effect: 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.Trinucleotide Repeat Expansion: An increased number of contiguous trinucleotide repeats in the DNA sequence from one generation to the next. The presence of these regions is associated with diseases such as FRAGILE X SYNDROME and MYOTONIC DYSTROPHY. Some CHROMOSOME FRAGILE SITES are composed of sequences where trinucleotide repeat expansion occurs.Neurofibromin 1: A protein found most abundantly in the nervous system. Defects or deficiencies in this protein are associated with NEUROFIBROMATOSIS 1, Watson syndrome, and LEOPARD syndrome. Mutations in the gene (GENE, NEUROFIBROMATOSIS 1) affect two known functions: regulation of ras-GTPase and tumor suppression.Introns: 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.Fanconi Anemia Complementation Group Proteins: A diverse group of proteins whose genetic MUTATIONS have been associated with the chromosomal instability syndrome FANCONI ANEMIA. Many of these proteins play important roles in protecting CELLS against OXIDATIVE STRESS.Mutagenesis: Process of generating a genetic MUTATION. It may occur spontaneously or be induced by MUTAGENS.Inheritance Patterns: The different ways GENES and their ALLELES interact during the transmission of genetic traits that effect the outcome of GENE EXPRESSION.Cilia: Populations of thin, motile processes found covering the surface of ciliates (CILIOPHORA) or the free surface of the cells making up ciliated EPITHELIUM. Each cilium arises from a basic granule in the superficial layer of CYTOPLASM. The movement of cilia propels ciliates through the liquid in which they live. The movement of cilia on a ciliated epithelium serves to propel a surface layer of mucus or fluid. (King & Stansfield, A Dictionary of Genetics, 4th ed)Software: Sequential operating programs and data which instruct the functioning of a digital computer.Transgenes: Genes that are introduced into an organism using GENE TRANSFER TECHNIQUES.Amino Acid Substitution: 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.Cystathionine beta-Synthase: A multifunctional pyridoxal phosphate enzyme. In the second stage of cysteine biosynthesis it catalyzes the reaction of homocysteine with serine to form cystathionine with the elimination of water. Deficiency of this enzyme leads to HYPERHOMOCYSTEINEMIA and HOMOCYSTINURIA. EC 4.2.1.22.RNA Splice Sites: Nucleotide sequences located at the ends of EXONS and recognized in pre-messenger RNA by SPLICEOSOMES. They are joined during the RNA SPLICING reaction, forming the junctions between exons.Genomics: The systematic study of the complete DNA sequences (GENOME) of organisms.Algorithms: A procedure consisting of a sequence of algebraic formulas and/or logical steps to calculate or determine a given task.Sequence Alignment: The arrangement of two or more amino acid or base sequences from an organism or organisms in such a way as to align areas of the sequences sharing common properties. The degree of relatedness or homology between the sequences is predicted computationally or statistically based on weights assigned to the elements aligned between the sequences. This in turn can serve as a potential indicator of the genetic relatedness between the organisms.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.X Chromosome: 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.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Evolution, Molecular: The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.Genetics, Population: 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.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.HeLa Cells: The first continuously cultured human malignant CELL LINE, derived from the cervical carcinoma of Henrietta Lacks. These cells are used for VIRUS CULTIVATION and antitumor drug screening assays.Haplotypes: 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.DNA Damage: Injuries to DNA that introduce deviations from its normal, intact structure and which may, if left unrepaired, result in a MUTATION or a block of DNA REPLICATION. These deviations may be caused by physical or chemical agents and occur by natural or unnatural, introduced circumstances. They include the introduction of illegitimate bases during replication or by deamination or other modification of bases; the loss of a base from the DNA backbone leaving an abasic site; single-strand breaks; double strand breaks; and intrastrand (PYRIMIDINE DIMERS) or interstrand crosslinking. Damage can often be repaired (DNA REPAIR). If the damage is extensive, it can induce APOPTOSIS.Karyotyping: Mapping of the KARYOTYPE of a cell.Protein Transport: The process of moving proteins from one cellular compartment (including extracellular) to another by various sorting and transport mechanisms such as gated transport, protein translocation, and vesicular transport.Myotonic Dystrophy: Neuromuscular disorder characterized by PROGRESSIVE MUSCULAR ATROPHY; MYOTONIA, and various multisystem atrophies. Mild INTELLECTUAL DISABILITY may also occur. Abnormal TRINUCLEOTIDE REPEAT EXPANSION in the 3' UNTRANSLATED REGIONS of DMPK PROTEIN gene is associated with Myotonic Dystrophy 1. DNA REPEAT EXPANSION of zinc finger protein-9 gene intron is associated with Myotonic Dystrophy 2.Genes: 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.Dogs: The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)Huntington Disease: A familial disorder inherited as an autosomal dominant trait and characterized by the onset of progressive CHOREA and DEMENTIA in the fourth or fifth decade of life. Common initial manifestations include paranoia; poor impulse control; DEPRESSION; HALLUCINATIONS; and DELUSIONS. Eventually intellectual impairment; loss of fine motor control; ATHETOSIS; and diffuse chorea involving axial and limb musculature develops, leading to a vegetative state within 10-15 years of disease onset. The juvenile variant has a more fulminant course including SEIZURES; ATAXIA; dementia; and chorea. (From Adams et al., Principles of Neurology, 6th ed, pp1060-4)Genomic Instability: An increased tendency of the GENOME to acquire MUTATIONS when various processes involved in maintaining and replicating the genome are dysfunctional.Mutation Rate: The number of mutations that occur in a specific sequence, GENE, or GENOME over a specified period of time such as years, CELL DIVISIONS, or generations.Oligonucleotide Array Sequence Analysis: Hybridization of a nucleic acid sample to a very large set of OLIGONUCLEOTIDE PROBES, which have been attached individually in columns and rows to a solid support, to determine a BASE SEQUENCE, or to detect variations in a gene sequence, GENE EXPRESSION, or for GENE MAPPING.Genetic Association Studies: 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.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Mosaicism: The occurrence in an individual of two or more cell populations of different chromosomal constitutions, derived from a single ZYGOTE, as opposed to CHIMERISM in which the different cell populations are derived from more than one zygote.Polymorphism, Genetic: 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.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Gene Expression Profiling: The determination of the pattern of genes expressed at the level of GENETIC TRANSCRIPTION, under specific circumstances or in a specific cell.Tumor Suppressor Proteins: Proteins that are normally involved in holding cellular growth in check. Deficiencies or abnormalities in these proteins may lead to unregulated cell growth and tumor development.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Alternative Splicing: A process whereby multiple RNA transcripts are generated from a single gene. Alternative splicing involves the splicing together of other possible sets of EXONS during the processing of some, but not all, transcripts of the gene. Thus a particular exon may be connected to any one of several alternative exons to form a mature RNA. The alternative forms of mature MESSENGER RNA produce PROTEIN ISOFORMS in which one part of the isoforms is common while the other parts are different.Mutagenesis, Insertional: Mutagenesis where the mutation is caused by the introduction of foreign DNA sequences into a gene or extragenic sequence. This may occur spontaneously in vivo or be experimentally induced in vivo or in vitro. Proviral DNA insertions into or adjacent to a cellular proto-oncogene can interrupt GENETIC TRANSLATION of the coding sequences or interfere with recognition of regulatory elements and cause unregulated expression of the proto-oncogene resulting in tumor formation.Internet: A loose confederation of computer communication networks around the world. The networks that make up the Internet are connected through several backbone networks. The Internet grew out of the US Government ARPAnet project and was designed to facilitate information exchange.Databases, Nucleic Acid: Databases containing information about NUCLEIC ACIDS such as BASE SEQUENCE; SNPS; NUCLEIC ACID CONFORMATION; and other properties. Information about the DNA fragments kept in a GENE LIBRARY or GENOMIC LIBRARY is often maintained in DNA databases.Germ-Line Mutation: Any detectable and heritable alteration in the lineage of germ cells. Mutations in these cells (i.e., "generative" cells ancestral to the gametes) are transmitted to progeny while those in somatic cells are not.Jews: An ethnic group with historical ties to the land of ISRAEL and the religion of JUDAISM.Fetus: The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.alpha 1-Antitrypsin: Plasma glycoprotein member of the serpin superfamily which inhibits TRYPSIN; NEUTROPHIL ELASTASE; and other PROTEOLYTIC ENZYMES.DNA, Mitochondrial: Double-stranded DNA of MITOCHONDRIA. In eukaryotes, the mitochondrial GENOME is circular and codes for ribosomal RNAs, transfer RNAs, and about 10 proteins.Gene Dosage: 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.Globins: A superfamily of proteins containing the globin fold which is composed of 6-8 alpha helices arranged in a characterstic HEME enclosing structure.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Retinitis Pigmentosa: Hereditary, progressive degeneration of the neuroepithelium of the retina characterized by night blindness and progressive contraction of the visual field.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Hematologic Diseases: Disorders of the blood and blood forming tissues.Bone Regeneration: Renewal or repair of lost bone tissue. It excludes BONY CALLUS formed after BONE FRACTURES but not yet replaced by hard bone.Phenylalanine Hydroxylase: An enzyme of the oxidoreductase class that catalyzes the formation of L-TYROSINE, dihydrobiopterin, and water from L-PHENYLALANINE, tetrahydrobiopterin, and oxygen. Deficiency of this enzyme may cause PHENYLKETONURIAS and PHENYLKETONURIA, MATERNAL. EC 1.14.16.1.Ethics, Medical: The principles of professional conduct concerning the rights and duties of the physician, relations with patients and fellow practitioners, as well as actions of the physician in patient care and interpersonal relations with patient families.Models, Animal: Non-human animals, selected because of specific characteristics, for use in experimental research, teaching, or testing.