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Human Y-chromosome DNA haplogroup

Human Y-DNA phylogeny and haplogroup distribution.[1](a) Phylogenetic tree. 'kya' means 'thousand years ago'. (b) Geographical distributions of haplogroups are shown in color. (c) Geographical color legend.

In human genetics, a human Y-chromosome DNA haplogroup is a haplogroup defined by specific mutations in the non-recombining portions of DNA on the male-specific Y chromosome (Y-DNA). Individuals within a haplogroup share similar numbers of short tandem repeats (STRs) and single-nucleotide polymorphisms (SNPs).[2] The Y-chromosome accumulates approximately two mutations per generation,[3] and Y-DNA haplogroups represent significant branches of the Y-chromosome phylogenetic tree, each characterized by hundreds or even thousands of unique mutations.

The Y-chromosomal most recent common ancestor (Y-MRCA), often referred to as Y-chromosomal Adam, is the most recent common ancestor from whom all currently living humans are descended patrilineally. Y-chromosomal Adam is estimated to have lived around 236,000 years ago in Africa[citation needed]. By examining other population bottlenecks, most Eurasian men trace their descent from a man who lived in Africa approximately 69,000 years ago (Haplogroup CT). Although Southeast Asia has been proposed as the origin for all non-African human Y chromosomes,[4] this hypothesis is considered unlikely.[5] Other bottlenecks occurred roughly 50,000 and 5,000 years ago, and the majority of Eurasian men are believed to be descended from four ancestors who lived 50,000 years ago, all of whom were descendants of an African lineage (Haplogroup E-M168).[6][7][8]

  1. ^ Hallast P, Agdzhoyan A, Balanovsky O, Xue Y, Tyler-Smith C (2020). "A Southeast Asian origin for present-day non-African human Y chromosomes". Human Genetics. 140 (2): 299–307. doi:10.1007/s00439-020-02204-9. PMC 7864842. PMID 32666166.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ "Understanding Haplogroups: How are the haplogroups named?". Family Tree DNA. Archived from the original on 21 June 2012. Retrieved 31 March 2013.
  3. ^ Dolgin, Elie (2009). "Human mutation rate revealed". Nature. doi:10.1038/news.2009.864. Retrieved 18 September 2017. "one mutation in every 30 million base pairs"
  4. ^ Hallast, Pille; Agdzhoyan, Anastasia; Balanovsky, Oleg; Xue, Yali; Tyler-Smith, Chris (2021). "A Southeast Asian origin for present-day non-African human Y chromosomes". Human Genetics. 140 (2): 299–307. doi:10.1007/s00439-020-02204-9. ISSN 0340-6717. PMC 7864842. PMID 32666166.
  5. ^ St. Clair, Michael (2021). The Prehistory of Language: A Triangulated Y-Chromosome-Based Perspective. Stuttgart, Germany: Genetic–Linguistic Interface. p. 29. ISBN 978-3-00-071045-2.
  6. ^ Karmin; et al. (2015). "A recent bottleneck of Y chromosome diversity coincides with a global change in culture". Genome Research. 25 (4): 459–66. doi:10.1101/gr.186684.114. PMC 4381518. PMID 25770088. "we date the Y-chromosomal most recent common ancestor (MRCA) in Africa at 254 (95% CI 192–307) kya and detect a cluster of major non-African founder haplogroups in a narrow time interval at 47–52 kya, consistent with a rapid initial colonization model of Eurasia and Oceania after the out-of-Africa bottleneck. In contrast to demographic reconstructions based on mtDNA, we infer a second strong bottleneck in Y-chromosome lineages dating to the last 10 ky. We hypothesize that this bottleneck is caused by cultural changes affecting variance of reproductive success among males."
  7. ^ Cite error: The named reference YFullYTree was invoked but never defined (see the help page).
  8. ^ "Something Weird Happened to Men 7,000 Years Ago, And We Finally Know Why". 31 May 2018. Around 7000 years ago - all the way back in the Neolithic - something really peculiar happened to human genetic diversity. Over the next 2,000 years, and seen across Africa, Europe and Asia, the genetic diversity of the Y chromosome collapsed, becoming as though there was only one man for every 17 women.

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