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28-457: Each haplogroup originates from, and remains part of, a preceding single haplogroup (or paragroup ). As such, any related group of haplogroups may be precisely modelled as a nested hierarchy , in which each set (haplogroup) is also a subset of a single broader set (as opposed, that is, to biparental models, such as human family trees). Haplogroups can be further divided into subclades. Haplogroups are normally identified by an initial letter of

56-442: A subclade is a subgroup of a haplogroup . Although human mitochondrial DNA (mtDNA) and Y chromosome DNA (Y-DNA) haplogroups and subclades are named in a similar manner, their names belong to completely separate systems. mtDNA haplogroups are defined by the presence of a series of single-nucleotide polymorphism (SNP) markers in the hypervariable regions and the coding region of mitochondrial DNA . They are named with

84-497: A direct female line of descent. Mutations are changes in the nitrogen bases of the DNA sequence . Single changes from the original sequence are called single nucleotide polymorphisms (SNPs). Human Y chromosomes are male-specific sex chromosomes ; nearly all humans that possess a Y chromosome will be morphologically male. Although Y chromosomes are situated in the cell nucleus and paired with X chromosomes , they only recombine with

112-439: A more recent haplogroup (which is a subgroup or subclade ) of its own to which humans carrying only mutation A do not belong. Both mtDNA and Y chromosomes are grouped into lineages and haplogroups; these are often presented as tree-like diagrams. Human Y chromosome DNA (Y-DNA) haplogroups are named from A to T, and are further subdivided using numbers and lower case letters. Y chromosome haplogroup designations are established by

140-694: A new name. Until the SNP/UEP marker M293 was discovered in 2008, the members of the subclade were indistinguishable from other components of the paragroup E1b1b1* (also known as E3b* and E-M35*). Another example is a member of the Y-DNA haplogroup R (defined by marker M207) may belong to the sub-haplogroup R1 (defined by marker M173) or R2 (defined by marker M124). Individuals with neither of these mutations would be categorised as belonging to haplogroup R*. Phylogenetic tree of human mitochondrial DNA (mtDNA) haplogroups Subclade In genetics ,

168-436: A set of ten Y chromosomes (derived from ten different individuals) contains a mutation, A, but only five of these chromosomes contain a second mutation, B, then it must be the case that mutation B occurred after mutation A. Furthermore, all ten individuals who carry the chromosome with mutation A are the direct male line descendants of the same man who was the first person to carry this mutation. The first man to carry mutation B

196-408: Is contained in the chromosomes in the nucleus of the cell, but mtDNA is an exception. An individual inherits their cytoplasm and the organelles contained by that cytoplasm exclusively from the maternal ovum (egg cell); sperm only pass on the chromosomal DNA, all paternal mitochondria are digested in the oocyte . When a mutation arises in a mtDNA molecule, the mutation is therefore passed down in

224-449: Is passed solely along the patrilineal line, from father to son, while mtDNA is passed down the matrilineal line, from mother to offspring of both sexes. Neither recombines , and thus Y-DNA and mtDNA change only by chance mutation at each generation with no intermixture between parents' genetic material. Mitochondria are small organelles that lie in the cytoplasm of eukaryotic cells , such as those of humans. Their primary function

252-412: Is to provide energy to the cell. Mitochondria are thought to be reduced descendants of symbiotic bacteria that were once free living. One indication that mitochondria were once free living is that each contains a circular DNA , called mitochondrial DNA (mtDNA), whose structure is more similar to bacteria than eukaryotic organisms (see endosymbiotic theory ). The overwhelming majority of a human's DNA

280-684: The Sami people . Here is a list of Y-chromosome and MtDNA geographic haplogroup assignment proposed by Bekada et al. 2013. According to SNPS haplogroups which are the age of the first extinction event tend to be around 45–50 kya. Haplogroups of the second extinction event seemed to diverge 32–35 kya according to Mal'ta . The ground zero extinction event appears to be Toba during which haplogroup CDEF* appeared to diverge into C, DE and F. C and F have almost nothing in common while D and E have plenty in common. Extinction event #1 according to current estimates occurred after Toba, although older ancient DNA could push

308-625: The Americas, and Melanesia, as well as in parts of the Horn of Africa and North Africa; almost none have been found in Europe. The N haplogroup may represent another macrolineage that evolved outside of Africa, heading northward instead of eastward. Shortly after the migration, the large R group split off from the N. Haplogroup R consists of two subgroups defined on the basis of their geographical distributions, one found in southeastern Asia and Oceania and

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336-1373: The Horn of Africa and the Arabian Peninsula (Saudi Arabia, Yemen, Oman), separated only by a narrow strait between the Red Sea and the Gulf of Aden. CZ – Many Siberians; branch C – Some Amerindian; branch Z – Many Saami, some Korean, some North Chinese, some Central Asian populations. D – Some Amerindians, many Siberians and northern East Asians E – Malay, Borneo, Philippines, Taiwanese aborigines , Papua New Guinea G – Many Northeast Siberians, northern East Asians, and Central Asians Q – Melanesian, Polynesian, New Guinean populations The N type consists of: A – Found in many Amerindians and some East Asians and Siberians I – 10% frequency in Northern, Eastern Europe S – Some Indigenous Australian (First Nations People of Australia) W – Some Eastern Europeans, South Asians, and southern East Asians X – Some Amerindians, Southern Siberians, Southwest Asians, and Southern Europeans Y – Most Nivkhs and people of Nias ; many Ainus, Tungusic people , and Austronesians ; also found with low frequency in some other populations of Siberia, East Asia, and Central Asia R – Large group found within

364-691: The Levant (modern Lebanon area), found in 25% frequency in Bedouin populations; branch JT (branch J; branch T) – North, Eastern Europe, Indus, Mediterranean U – High frequency in West Eurasia, Indian sub-continent, and Algeria, found from India to the Mediterranean and to the rest of Europe; U5 in particular shows high frequency in Scandinavia and Baltic countries with the highest frequency in

392-855: The N type. Populations contained therein can be divided geographically into West Eurasia and East Eurasia. Almost all European populations and a large number of Middle-Eastern population today are contained within this branch. A smaller percentage is contained in other N type groups (See above). Below are subclades of R : B – Some Chinese, Tibetans, Mongolians, Central Asians, Koreans, Amerindians, South Siberians, Japanese, Austronesians F – Mainly found in southeastern Asia, especially Vietnam ; 8.3% in Hvar Island in Croatia. R0 – Found in Arabia and among Ethiopians and Somalis; branch HV (branch H; branch V) – Europe, Western Asia, North Africa; Pre-JT – Arose in

420-467: The X chromosome at the ends of the Y chromosome ; the remaining 95% of the Y chromosome does not recombine. Therefore, the Y chromosome and any mutations that arise in it are passed down in a direct male line of descent. Other chromosomes, autosomes and X chromosomes (when another X chromosome is available to pair with it), share their genetic material during meiosis , the process of cell division which produces gametes . Effectively this means that

448-714: The Y Chromosome Consortium. Y-chromosomal Adam is the name given by researchers to the male who is the most recent common patrilineal (male-lineage) ancestor of all living humans. Major Y-chromosome haplogroups, and their geographical regions of occurrence (prior to the recent European colonization), include: (mutation M168 occurred ~50,000 bp) (mutation M89 occurred ~45,000 bp) (mutation M9 occurred ~40,000 bp ) Human mtDNA haplogroups are lettered: A , B , C , CZ , D , E , F , G , H , HV , I , J , pre- JT , JT , K , L0 , L1 , L2 , L3 , L4 , L5 , L6 , M , N , O , P , Q , R , R0 , S , T , U , V , W , X , Y , and Z . The most up-to-date version of

476-417: The alphabet, and refinements consist of additional number and letter combinations, such as (for example) A → A1 → A1a . The alphabetical nomenclature was published in 2002 by the Y Chromosome Consortium . In human genetics , the haplogroups most commonly studied are Y-chromosome (Y-DNA) haplogroups and mitochondrial DNA (mtDNA) haplogroups , each of which can be used to define genetic populations . Y-DNA

504-445: The capital letters A through T, with further subclades named using numbers and lower case letters (YCC longhand nomenclature ). YCC shorthand nomenclature names Y-DNA haplogroups and their subclades with the first letter of the major Y-DNA haplogroup followed by a dash and the name of the defining terminal SNP. Y-DNA haplogroup nomenclature is changing over time to accommodate the increasing number of SNPs being discovered and tested, and

532-457: The capital letters A through Z, with further subclades named using numbers and lower case letters. Y-DNA haplogroups are defined by the presence of a series of SNP markers on the Y chromosome . Subclades are defined by a terminal SNP , the SNP furthest down in the Y chromosome phylogenetic tree. The Y Chromosome Consortium (YCC) developed a system of naming major human Y-DNA haplogroups with

560-559: The following are common divisions for mtDNA haplogroups: The mitochondrial haplogroups are divided into three main groups, which are designated by the sequential letters L, M, N. Humanity first split within the L group between L0 and L1-6. L1-6 gave rise to other L groups, one of which, L3, split into the M and N group. The M group comprises the first wave of human migration which is thought to have evolved outside of Africa, following an eastward route along southern coastal areas. Descendant lineages of haplogroup M are now found throughout Asia,

588-487: The genetic material from these chromosomes gets mixed up in every generation, and so any new mutations are passed down randomly from parents to offspring. The special feature that both Y chromosomes and mtDNA display is that mutations can accrue along a certain segment of both molecules and these mutations remain fixed in place on the DNA. Furthermore, the historical sequence of these mutations can also be inferred. For example, if

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616-414: The ground zero extinction event to long before Toba, and push the first extinction event here back to Toba. Haplogroups with extinction event notes by them have a dubious origin and this is because extinction events lead to severe bottlenecks, so all notes by these groups are just guesses. Note that the SNP counting of ancient DNA can be highly variable meaning that even though all these groups diverged around

644-472: The mtDNA tree is maintained by Mannis van Oven on the PhyloTree website. Phylogenetic tree of human mitochondrial DNA (mtDNA) haplogroups Mitochondrial Eve is the name given by researchers to the woman who is the most recent common matrilineal (female-lineage) ancestor of all living humans. Haplogroups can be used to define genetic populations and are often geographically oriented. For example,

672-458: The other containing almost all of the modern European populations. Haplogroup N(xR), i.e. mtDNA that belongs to the N group but not to its R subgroup, is typical of Australian aboriginal populations, while also being present at low frequencies among many populations of Eurasia and the Americas. The L type consists of nearly all Africans. The M type consists of: M1 – Ethiopian, Somali and Indian populations. Likely due to much gene flow between

700-421: The paragroup to form an independent subclade. For example, the paragroup of human Y-DNA Haplogroup DE is DE*. A member of DE* has the marker that defines DE, but not the markers that define DE's only known immediate subclades, haplogroups D and E . Likewise, haplogroup E1b1b1g (also known as E-M293) is an example of a relatively new subclade, discovered within a previously designated paragroup and assigned

728-406: The same time no one knows when. Y-Chromosome Paragroup Paragroup is a term used in population genetics to describe lineages within a haplogroup that are not defined by any additional unique markers . In human Y-chromosome DNA haplogroups , paragroups are typically represented by an asterisk ( * ) placed after the main haplogroup. The term "paragroup" is a portmanteau of

756-412: The terms paraphyletic haplogroup indicating that paragroups form paraphyletic subclades. Apart from the mutations that define the parent haplogroup, paragroups may not possess any additional unique markers. Alternatively paragroups may possess unique markers that have not been discovered. If a unique marker is discovered within a paragroup, the specific lineage is given a unique name and is moved out of

784-422: Was also a direct male line descendant of this man, but is also the direct male line ancestor of all men carrying mutation B. Series of mutations such as this form molecular lineages. Furthermore, each mutation defines a set of specific Y chromosomes called a haplogroup. All humans carrying mutation A form a single haplogroup, and all humans carrying mutation B are part of this haplogroup, but mutation B also defines

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