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Genocopy
Genocopy is a trait that is a phenotypic copy of a genetic trait but is caused by a different genotype. When a genetic mutation or genotype in one locus results in a phenotype similar to one that is known to be caused by another mutation or genotype in another locus, it is said to be a genocopy. However, genocopies may also be referred to as "genetic mimics", in which the same mutation or specific genotype can result in two unique phenotypes in two different patients. The term “Genocopy” was coined by Dr. H. Nachstheim in 1957, in which he discusses “false” phenocopies. In comparison to when a phenotype is the result of an environmental condition that had the same effect as a previously known genetic factor such as mutation. While offspring may inherit specific mutations or genotypes that result in genocopies, phenocopies are not heritable. Two types of elliptocytosis that are genocopies of each other, but are distinguished by the fact that one is linked to the Rh blood grou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenocopy
A phenocopy is a variation in phenotype (generally referring to a single trait) which is caused by environmental conditions (often, but not necessarily, during the organism's development), such that the organism's phenotype matches a phenotype which is determined by genetic factors. It is not a type of mutation, as it is non-hereditary. The term was coined by Richard Goldschmidt in 1935. He used it to refer to forms, produced by some experimental procedure, whose appearance duplicates or copies the phenotype of some mutant or combination of mutants. Examples The butterfly genus ''Vanessa'' can change phenotype based on the local temperature. If introduced to Lapland they mimic butterflies localised to this area; and if localised to Syria they mimic butterflies of this area. The larvae of ''Drosophila melanogaster'' have been found to be particularly vulnerable to environmental factors which produce phenocopies of known mutations; these factors include temperature, shock, radiati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TBX1
T-box transcription factor TBX1 also known as T-box protein 1 and testis-specific T-box protein is a protein that in humans is encoded by the TBX1 gene. Genes in the T-box family are transcription factors that play important roles in the formation of tissues and organs during embryonic development. To carry out these roles, proteins made by this gene family bind to specific areas of DNA called T-box binding element (TBE) to control the expression of target genes. Gene The TBX1 gene is located on the long (q) arm of chromosome 22 at position 11.21, from base pair 18,118,779 to base pair 18,145,669. Function The T-box 1 protein appears to be necessary for the normal development of large arteries that carry blood out of the heart, muscles and bones of the face and neck, and glands such as the thymus and parathyroid. Although the T-box 1 protein acts as a transcription factor, it is not yet known which genes are regulated by the protein. Clinical significance Most cases of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thymine
Thymine () ( symbol T or Thy) is one of the four nucleobases in the nucleic acid of DNA that are represented by the letters G–C–A–T. The others are adenine, guanine, and cytosine. Thymine is also known as 5-methyluracil, a pyrimidine nucleobase. In RNA, thymine is replaced by the nucleobase uracil. Thymine was first isolated in 1893 by Albrecht Kossel and Albert Neumann from calf thymus glands, hence its name. Derivation As its alternate name (5-methyluracil) suggests, thymine may be derived by methylation of uracil at the 5th carbon. In RNA, thymine is replaced with uracil in most cases. In DNA, thymine (T) binds to adenine (A) via two hydrogen bonds, thereby stabilizing the nucleic acid structures. Thymine combined with deoxyribose creates the nucleoside deoxythymidine, which is synonymous with the term thymidine. Thymidine can be phosphorylated with up to three phosphoric acid groups, producing dTMP (deoxythymidine monophosphate), dTDP, or dTTP (for the di- and tr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytosine
Cytosine () ( symbol C or Cyt) is one of the four nucleobases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2). The nucleoside of cytosine is cytidine. In Watson-Crick base pairing, it forms three hydrogen bonds with guanine. History Cytosine was discovered and named by Albrecht Kossel and Albert Neumann in 1894 when it was hydrolyzed from calf thymus tissues. A structure was proposed in 1903, and was synthesized (and thus confirmed) in the laboratory in the same year. In 1998, cytosine was used in an early demonstration of quantum information processing when Oxford University researchers implemented the Deutsch-Jozsa algorithm on a two qubit nuclear magnetic resonance quantum computer (NMRQC). In March 2015, NASA scientists reported the formation of cytosine, along with uracil and thym ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transactivation Domain
The transactivation domain or trans-activating domain (TAD) is a transcription factor scaffold domain which contains binding sites for other proteins such as transcription coregulators. These binding sites are frequently referred to as activation functions (AFs). TADs are named after their amino acid composition. These amino acids are either essential for the activity or simply the most abundant in the TAD. Transactivation by the Gal4 transcription factor is mediated by acidic amino acids, whereas hydrophobic residues in Gcn4 play a similar role. Hence, the TADs in Gal4 and Gcn4 are referred to as acidic or hydrophobic, respectively. In general we can distinguish four classes of TADs: * acidic domains (called also “acid blobs” or “negative noodles", rich in D and E amino acids, present in Gal4, Gcn4 and VP16). * glutamine-rich domains (contains multiple repetitions like "QQQXXXQQQ", present in SP1) * proline-rich domains (contains repetitions like "PPPXXXPPP" present in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
De Novo Mutation
A de novo mutation is any mutation/alteration in the genome of any organism (humans, animals, plant, microbes, etc.) that wasn't present or transmitted by their parents. This type of mutation (like any other) occurs spontaneously during the process of DNA replication during cell division in a fetus whose close, biological relatives don't have the mutation. Often, these kind of mutations have very little to no effect on the affected organism, but in rare cases they have a notable and/or serious effect on overall health, physical appearance, etc. Rate The average number of spontaneous mutations (not present in the parents) an infant has in its genome is approximately 43.86 DNMs. A study done in September of 2019 by the University of Utah Health revealed that certain families have a higher spontaneous mutation rate than average, meaning that their newborns had more spontaneous mutations (not present in their parents) than the average newborn, this tendency was found to be hereditar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Duplication (chromosomal)
Gene duplication (or chromosomal duplication or gene amplification) is a major mechanism through which new genetic material is generated during molecular evolution. It can be defined as any duplication of a region of DNA that contains a gene. Gene duplications can arise as products of several types of errors in DNA replication and repair machinery as well as through fortuitous capture by selfish genetic elements. Common sources of gene duplications include ectopic recombination, retrotransposition event, aneuploidy, polyploidy, and replication slippage. Mechanisms of duplication Ectopic recombination Duplications arise from an event termed unequal crossing-over that occurs during meiosis between misaligned homologous chromosomes. The chance of it happening is a function of the degree of sharing of repetitive elements between two chromosomes. The products of this recombination are a duplication at the site of the exchange and a reciprocal deletion. Ectopic recombination is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deletion (genetics)
In genetics, a deletion (also called gene deletion, deficiency, or deletion mutation) (sign: Δ) is a mutation (a genetic aberration) in which a part of a chromosome or a sequence of DNA is left out during DNA replication. Any number of nucleotides can be deleted, from a single base to an entire piece of chromosome. Some chromosomes have fragile spots where breaks occur which result in the deletion of a part of chromosome. The breaks can be induced by heat, viruses, radiations, chemicals. When a chromosome breaks, a part of it is deleted or lost, the missing piece of chromosome is referred to as deletion or a deficiency. For synapsis to occur between a chromosome with a large intercalary deficiency and a normal complete homolog, the unpaired region of the normal homolog must loop out of the linear structure into a deletion or compensation loop. The smallest single base deletion mutations occur by a single base flipping in the template DNA, followed by template DNA strand sli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DiGeorge Syndrome
DiGeorge syndrome, also known as 22q11.2 deletion syndrome, is a syndrome caused by a microdeletion on the long arm of chromosome 22. While the symptoms can vary, they often include congenital heart problems, specific facial features, frequent infections, developmental delay, learning problems and cleft palate. Associated conditions include kidney problems, schizophrenia, hearing loss and autoimmune disorders such as rheumatoid arthritis or Graves' disease. DiGeorge syndrome is typically due to the deletion of 30 to 40 genes in the middle of chromosome 22 at a location known as ''22q11.2''. About 90% of cases occur due to a new mutation during early development, while 10% are inherited from a person's parents. It is autosomal dominant, meaning that only one affected chromosome is needed for the condition to occur. Diagnosis is suspected based on the symptoms and confirmed by genetic testing. Although there is no cure, treatment can improve symptoms. This often includes a m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
22q11
Q11 may refer to: * Q11 (New York City bus) * , a survey ship of the Argentine Navy * DZOE-TV, formerly Q-11 * , an armed yacht of the Royal Canadian Navy * Hud (surah) Hud ( ar, هود, ), is the 11th chapter (''Surah'') of the Quran and has 123 verses ('' ayat''). It relates in part to the prophet Hud. Regarding the timing and contextual background of the revelation (''asbāb al-nuzūl''), it is an earlier " ..., of the Quran * Motorola Q11, a Motorola smartphone {{Letter-NumberCombDisambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotypic
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology or physical form and structure, its developmental processes, its biochemical and physiological properties, its behavior, and the products of behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code, or its genotype, and the influence of environmental factors. Both factors may interact, further affecting phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and then again in his 1982 book ''The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
