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HVR1
A hypervariable region (HVR) is a location within a sequence where polymorphisms frequently occur. It is used in two contexts: * In the case of nucleic acids, an HVR is where base pairs frequently change. This can be due to a change in the number of repeats (which is seen in eukaryotic nuclear DNA) or simply low selective pressure allowing a great number of substitutions and indels (as in the case of mitochondrial DNA D-loop and 16S rRNA). * In the case of antibodies, an HVR is where most of the differences among antibodies occur. This region is also called the complementarity-determining region. Because there already is a separate article for the antibody region, this article will focus on the nucleic acid case. Mitochondrial There are two mitochondrial hypervariable regions used in human mitochondrial genealogical DNA testing. HVR1 is considered a "low resolution" region and HVR2 is considered a "high resolution" region. Getting HVR1 and HVR2 DNA tests can help determine one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genealogical DNA Test
A genealogical DNA test is a DNA-based Genetic testing, genetic test used in genetic genealogy that looks at specific locations of a person's genome in order to find or verify ancestral genealogical relationships, or (with lower reliability) to estimate the ethnicity, ethnic mixture of an individual. Since different testing companies use different ethnic reference groups and different matching algorithms, ethnicity estimates for an individual vary between tests, sometimes dramatically. Three principal types of genealogical DNA tests are available, with each looking at a different part of the genome and being useful for different types of genealogical research: Genealogical DNA test#Autosomal DNA (atDNA) testing, autosomal (atDNA), Genealogical DNA test#Mitochondrial DNA (mtDNA) testing, mitochondrial (mtDNA), and Genealogical DNA test#Y-chromosome (Y-DNA) testing, Y-chromosome (Y-DNA). Autosomal tests may result in a large number of DNA matches to both males and females who have ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Genealogy
Genetic genealogy is the use of genealogical DNA tests, i.e., DNA profiling and DNA testing, in combination with traditional genealogical methods, to infer genetic relationships between individuals. This application of genetics came to be used by family historians in the 21st century, as DNA tests became affordable. The tests have been promoted by amateur groups, such as Surname DNA project, surname study groups or regional genealogical groups, as well as research projects such as the Genographic Project. about 30 million people had been tested. As the field developed, the aims of practitioners broadened, with many seeking knowledge of their ancestry beyond the recent centuries, for which traditional pedigrees can be constructed. History The investigation of surnames in 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial DNA
Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in a eukaryotic cell; most of the DNA is in the cell nucleus, and, in plants and algae, the DNA also is found in plastids, such as chloroplasts. Mitochondrial DNA is responsible for coding of 13 essential subunits of the complex oxidative phosphorylation (OXPHOS) system which has a role in cellular energy conversion. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that human mtDNA has 16,569 base pairs and encodes 13 proteins. As in other vertebrates, the human mitochondrial genetic code differs slightly from nuclear DNA. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (biology)
In biology, polymorphism is the occurrence of two or more clearly different morphs or forms, also referred to as alternative '' phenotypes'', in the population of a species. To be classified as such, morphs must occupy the same habitat at the same time and belong to a panmictic population (one with random mating). Ford E.B. 1965. ''Genetic polymorphism''. Faber & Faber, London. Put simply, polymorphism is when there are two or more possibilities of a trait on a gene. For example, there is more than one possible trait in terms of a jaguar's skin colouring; they can be light morph or dark morph. Due to having more than one possible variation for this gene, it is termed 'polymorphism'. However, if the jaguar has only one possible trait for that gene, it would be termed "monomorphic". For example, if there was only one possible skin colour that a jaguar could have, it would be termed monomorphic. The term polyphenism can be used to clarify that the different forms arise from the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MtDNA Control Region
A mitochondrion is a specialized organelle found in the cytoplasm of eukaryotic cells, which is the powerhouse of cells that produce energy through oxidative phosphorylation. Besides producing energy, they are crucial for various cellular functions such as calcium signaling, controlling metabolism, synthesizing hemoglobin and steroids, and regulating programmed cell death. Besides the production of ATP, there is a complex relationship between the mitochondrial genome (mtDNA) and the nuclear genome (nDNA). Unlike nuclear DNA which resides in the nucleus, mtDNA is inherited from the mother. Upon fertilization, the mtDNA of the sperm is typically lost through ubiquitination, and only the egg contributes to the mtDNA of the zygote, due to the significant difference in mtDNA copy number between the sperm (about 100 copies) and the egg (about 100,000 copies). Mitochondrial DNA (mtDNA) Is a small, abundant, and purified molecule of DNA. It is a closed, circular, double-stranded molecu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsatellite
A microsatellite is a tract of repetitive DNA in which certain Sequence motif, DNA motifs (ranging in length from one to six or more base pairs) are repeated, typically 5–50 times. Microsatellites occur at thousands of locations within an organism's genome. They have a higher mutation rate than other areas of DNA leading to high genetic diversity. Microsatellites are often referred to as short tandem repeats (STRs) by forensic genetics, forensic geneticists and in genetic genealogy, or as simple sequence repeats (SSRs) by plant geneticists. Microsatellites and their longer cousins, the minisatellites, together are classified as variable number tandem repeat, VNTR (variable number of tandem repeats) DNA. The name Satellite DNA, "satellite" DNA refers to the early observation that centrifugation of genomic DNA in a test tube separates a prominent layer of bulk DNA from accompanying "satellite" layers of repetitive DNA. They are widely used for DNA profiling in Loss of heterozygos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zoological Science
Zoology ( , ) is the scientific study of animals. Its studies include the structure, embryology, classification, habits, and distribution of all animals, both living and extinction">extinct, and how they interact with their ecosystems. Zoology is one of the primary branches of biology. The term is derived from Ancient Greek , ('animal'), and , ('knowledge', 'study'). Although humans have always been interested in the natural history of the animals they saw around them, and used this knowledge to domesticate certain species, the formal study of zoology can be said to have originated with Aristotle. He viewed animals as living organisms, studied their structure and development, and considered their adaptations to their surroundings and the function of their parts. Modern zoology has its origins during the Renaissance and early modern period, with Carl Linnaeus, Antonie van Leeuwenhoek, Robert Hooke, Charles Darwin, Gregor Mendel and many others. The study of animals has larg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subspecies
In Taxonomy (biology), biological classification, subspecies (: subspecies) is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (Morphology (biology), morphology), but that can successfully interbreed. Not all species have subspecies, but for those that do there must be at least two. Subspecies is abbreviated as subsp. or ssp. and the singular and plural forms are the same ("the subspecies is" or "the subspecies are"). In zoology, under the International Code of Zoological Nomenclature, the subspecies is the only taxonomic rank below that of species that can receive a name. In botany and mycology, under the International Code of Nomenclature for algae, fungi, and plants, other infraspecific name, infraspecific ranks, such as variety (botany), variety, may be named. In bacteriology and virology, under standard International Code of Nomenclature of Prokaryotes, bacterial nomenclature and virus clas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication ( translesion synthesis). Mutations may also result from substitution, insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics ( phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Asia
East Asia is a geocultural region of Asia. It includes China, Japan, Mongolia, North Korea, South Korea, and Taiwan, plus two special administrative regions of China, Hong Kong and Macau. The economies of Economy of China, China, Economy of Japan, Japan, Economy of South Korea, South Korea, and Economy of Taiwan, Taiwan are among the world's largest and most prosperous. East Asia borders North Asia to the north, Southeast Asia to the south, South Asia to the southwest, and Central Asia to the west. To its east is the Pacific Ocean. East Asia, especially History of China, Chinese civilization, is regarded as one of the earliest Cradle of civilization#China, cradles of civilization. Other ancient civilizations in East Asia that still exist as independent countries in the present day include the History of Japan, Japanese, History of Korea, Korean, and History of Mongolia, Mongolian civilizations. Various other civilizations existed as independent polities in East Asia in the past ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ayu Sweetfish
The ayu sweetfish (''Plecoglossus altivelis''), or sweetfish, is a species of fish. It is the only species in the genus ''Plecoglossus'' and family (biology), family Plecoglossidae. It is a relative of the Smelt (fish), smelts and other fish in the order Osmeriformes. Native to East Asia, it is distributed in the northwestern Pacific Ocean along the coast of Hokkaidō in Japan southward to the Korean Peninsula, China, Hong Kong and northern Vietnam. It is amphidromous, moving between coastal marine waters and freshwater lakes and rivers. A few landlocked populations also exist in lakes in Japan such as Lake Biwa, Biwa. Original wild populations in Taiwan became extinct in 1968 due to pollution and present extant populations were reintroduced from Japan in the 1990s. The name "sweetfish" was inspired by the sweetness of its flesh. In reference to its typical one-year lifespan, it is also written as ("year-fish"). [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
