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YAP (genetics)
Haplogroup DE is a human Y-chromosome DNA haplogroup. It is defined by the single nucleotide polymorphism (SNP) mutations, or UEPs, M1(YAP), M145(P205), M203, P144, P153, P165, P167, P183. DE is unique because it is distributed in several geographically distinct clusters. An immediate subclade, haplogroup D (also known as D-CTS3946), is mainly found in East Asia, parts of Central Asia, and the Andaman Islands, but also sporadically in West Africa and West Asia. The other immediate subclade, haplogroup E, is common in Africa, and to a lesser extent the Middle East and southern Europe. The most well-known unique event polymorphism (UEP) that defines DE is the Y-chromosome Alu Polymorphism "YAP''"''. The mutation was caused when a strand of DNA, known as Alu, inserted a copy of itself into the Y chromosome. Hence, all Y chromosomes belonging to DE, D, E and their subclades are YAP-positive (YAP+). All Y chromosomes that belong to other haplogroups and subclades are YAP-negative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Africa
Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area.Sayre, April Pulley (1999), ''Africa'', Twenty-First Century Books. . With nearly billion people as of , it accounts for about of the world's human population. Demographics of Africa, Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including Geography of Africa, geography, Climate of Africa, climate, corruption, Scramble for Africa, colonialism, the Cold War, and neocolonialism. Despite this lo ... [...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] |
Cameroon
Cameroon, officially the Republic of Cameroon, is a country in Central Africa. It shares boundaries with Nigeria to the west and north, Chad to the northeast, the Central African Republic to the east, and Equatorial Guinea, Gabon, and the Republic of the Congo to the south. Its coastline lies on the Bight of Biafra, part of the Gulf of Guinea, and the Atlantic Ocean. Due to its strategic position at the crossroads between West Africa and Central Africa, it has been categorized as being in both camps. Cameroon's population of nearly 31 million people speak 250 native languages, in addition to the national tongues of English and French, or both. Early inhabitants of the territory included the Sao civilisation around Lake Chad and the Baka people (Cameroon and Gabon), Baka hunter-gatherers in the southeastern rainforest. Portuguese discoveries, Portuguese explorers reached the coast in the 15th century and named the area ''Rio dos Camarões'' (''Shrimp River''), which became ''C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup R1b (Y-DNA)
Haplogroup R1b (R-M343), previously known as Hg1 and Eu18, is a Human Y-chromosome DNA haplogroup, human Y-chromosome haplogroup. It is the most frequently occurring paternal lineage in Western Europe, as well as some parts of Russia (e.g. the Bashkirs) and across the Sahel in Central Africa, namely: Cameroon, Chad, Guinea, Mauritania, Mali, Niger, Nigeria and Senegal (concentrated in parts of Chad with concentration in the Hausa people, Hausa Tribe and among the Chadic-speaking ethnic groups of Cameroon). The clade is also present at lower frequencies throughout Eastern Europe, Western Asia, Central Asia as well as parts of North Africa, South Asia and Central Asia. R1b has two primary branches: R1b1-L754 and R1b2-PH155. R1b1-L754 has two major subclades: R1b1a1b-M269, which predominates in Western Europe, and R1b1a2-V88, which is today common in parts of Central Africa. The other branch, R1b2-PH155, is so rare and widely dispersed that it is difficult to draw any conclusion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Most Recent Common Ancestor
A most recent common ancestor (MRCA), also known as a last common ancestor (LCA), is the most recent individual from which all organisms of a set are inferred to have descended. The most recent common ancestor of a higher taxon is generally assumed to have been a species. The term is also used in reference to the ancestry of groups of genes (haplotypes) rather than organisms. The ancestry of a set of individuals can sometimes be determined by referring to an established pedigree, although this may refer only to patrilineal or matrilineal lines for sexually-reproducing organisms with two parents, four grandparents, etc. However, in general, it is impossible to identify the exact MRCA of a large set of individuals, but an estimate of the time at which the MRCA lived can often be given. Such ''time to most recent common ancestor'' (''TMRCA'') estimates can be given based on DNA test results and established mutation rates as practiced in genetic genealogy, or by reference to a non- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tibet
Tibet (; ''Böd''; ), or Greater Tibet, is a region in the western part of East Asia, covering much of the Tibetan Plateau and spanning about . It is the homeland of the Tibetan people. Also resident on the plateau are other ethnic groups such as Mongols, Monpa people, Monpa, Tamang people, Tamang, Qiang people, Qiang, Sherpa people, Sherpa, Lhoba people, Lhoba, and since the 20th century Han Chinese and Hui people, Hui. Tibet is the highest region on Earth, with an average elevation of . Located in the Himalayas, the highest elevation in Tibet is Mount Everest, Earth's highest mountain, rising above sea level. The Tibetan Empire emerged in the 7th century. At its height in the 9th century, the Tibetan Empire extended far beyond the Tibetan Plateau, from the Tarim Basin and Pamirs in the west, to Yunnan and Bengal in the southeast. It then divided into a variety of territories. The bulk of western and central Tibet (Ü-Tsang) was often at least nominally unified under a ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guinea-Bissau
Guinea-Bissau, officially the Republic of Guinea-Bissau, is a country in West Africa that covers with an estimated population of 2,026,778. It borders Senegal to Guinea-Bissau–Senegal border, its north and Guinea to Guinea–Guinea-Bissau border, its southeast. Guinea-Bissau was once part of the kingdom of Kaabu, as well as part of the Mali Empire. Parts of this kingdom persisted until the 18th century, while a few others had been under some rule by the Portuguese Empire since the 16th century. In the 19th century, it was colonised as Portuguese Guinea. Portuguese control was restricted and weak until the early 20th century, when its pacification campaigns solidified Portuguese sovereignty in the area. The final Portuguese victory over the last remaining bastion of mainland resistance came in 1915, with the conquest of the Papel people, Papel-ruled Kingdom of Bissau by the Portuguese military officer João Teixeira Pinto, Teixeira Pinto and the Wolof people, Wolof mercenary ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nigeria
Nigeria, officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf of Guinea in the Atlantic Ocean to the south. It covers an area of . With Demographics of Nigeria, a population of more than 230 million, it is the List of African countries by population, most populous country in Africa, and the List of countries and dependencies by population, world's sixth-most populous country. Nigeria borders Niger in Niger–Nigeria border, the north, Chad in Chad–Nigeria border, the northeast, Cameroon in Cameroon–Nigeria border, the east, and Benin in Benin–Nigeria border, the west. Nigeria is a Federation, federal republic comprising 36 States of Nigeria, states and the Federal Capital Territory, Nigeria, Federal Capital Territory, where its capital, Abuja, is located. The List of Nigerian cities by population, largest city in Nigeria by population is Lagos, one of the largest List of largest cities, metr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup D (Y-DNA)
Haplogroup D, also known as D-CTS3946, is a Y-chromosome haplogroup. Like its relative distant sibling, haplogroup Haplogroup E (Y-DNA), E-M96, D-CTS3946 has the YAP+ unique-event polymorphism, which defines their parent, haplogroup DE. D-CTS3946 has two basal branches, Haplogroup D1, D1 and Haplogroup D2, D2. D1 and D2 are found primarily in East Asia, at low frequency in Central Asia and Southeast Asia, and at very low frequency in Western Africa and Western Asia. Origins Haplogroup D was formerly the name of the D lineage Haplogroup D-M174, D-M174. Varying proposals exist regarding the origin of haplogroup DE, the parent of D, with some suggesting an African and others an Asian origin. But D-M174 was, and generally is, assumed to be of Asian origin and is exclusively found in Asia. Haber et al. (2019) identified a haplogroup, termed "D0", in three Nigerians. Defined by the Single-nucleotide polymorphism, SNP A5580.2, "D0" haplogroup is outside M174, but belongs to the D li ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup B (Y-DNA)
Haplogroup B (M60) is a human Y-chromosome DNA haplogroup common to paternal lineages in Africa. It is a primary branch of the haplogroup BT. B (M60) is common in parts of Africa, especially the tropical forests of West-Central Africa. It was the ancestral haplogroup of not only modern Pygmies like the Baka and Mbuti, but also Hadzabe from Tanzania, who often have been considered, in large part because of some typological features of their language, to be a remnant of Khoisan people in East Africa. Distribution According to one study of the Y-DNA of populations in Sudan, haplogroup B-M60 is found in approximately 30% (16/53) of Southern Sudanese, 16% (5/32) of local Hausa people, 14% (4/28) of the Nuba of central Sudan, 3.7% (8/216) of Northern Sudanese (but only among Copts and Nubians), and 2.2% (2/90) of Western Sudanese. According to another study, haplogroup B is found in approximately 15% of Sudanese males, including 12.5% (5/40) B2a1a1a1 (M109/M152) and 2.5% (1/40) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup A (Y-DNA)
Haplogroup A is a human Y-chromosome DNA haplogroup, which includes all living human Y chromosomes. Bearers of extant sub-clades of haplogroup A are almost exclusively found in Africa (or among the African diaspora), in contrast with haplogroup BT, bearers of which participated in the Out of Africa migration of early modern humans. The known branches of haplogroup A are A00, A0, A1a, and A1b1; these branches are only very distantly related, and are not more closely related to each other than they are to haplogroup BT. Origin Though there are terminological challenges to define it as a haplogroup, haplogroup A has come to mean "the foundational haplogroup" (viz. of contemporary human populations); it is not defined by any mutation, but refers to any haplogroup which is not descended from the haplogroup BT; in other words, it is defined by the absence of the defining mutation of that group (M91). By this definition, haplogroup A includes all mutations that took place betw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Y-DNA Tree
The Y chromosome is one of two sex chromosomes in therian mammals and other organisms. Along with the X chromosome, it is part of the XY sex-determination system, in which the Y is the sex-determining chromosome because the presence of the Y chromosome causes offspring produced in sexual reproduction to be of male sex. In mammals, the Y chromosome contains the SRY gene, which triggers development of male gonads. The Y chromosome is passed only from male parents to male offspring. Overview Discovery The Y chromosome was identified as a sex-determining chromosome by Nettie Stevens at Bryn Mawr College in 1905 during a study of the mealworm ''Tenebrio molitor''. Edmund Beecher Wilson independently discovered the same mechanisms the same year, working with Hemiptera. Stevens proposed that chromosomes always existed in pairs and that the smaller chromosome (now labelled "Y") was the pair of the X chromosome discovered in 1890 by Hermann Henking. She realized that the previous id ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
