Haplogroup K (Y-DNA)

Jump to navigation Jump to search

In human genetics, Haplogroup K (M9) is a Human Y-chromosome DNA haplogroup.

It first appeared approximately 40,000 years ago in Iran or southern Central Asia. Today, haplogroup K and its descendant haplogroups are the patrilineal ancestors of most of the people living in the Northern Hemisphere, including most Europeans, Asians, and Native Americans. Other lineages derived from Haplogroup K are found among Melanesian populations, indicating an ancient link between most Eurasians and some populations of Oceania.

This haplogroup is a descendant of Haplogroup F (M89). Its major descendant haplogroups are K2 (M70), L (M20), M (M4), NO (M214) (plus NO's descendants N and O), and P (M45) (plus P's descendants Q and R). Haplogroups K1, K3, K4, K5, K6, and K7 are found only at low frequency among various populations of Eurasia, Oceania, and northern Africa.

Its subgroup K2 (M70) is present at a low level throughout Africa, Southwest Asia, South Asia, and Southern Europe, and, at an even lower level, throughout Europe. A famous member of the K2 haplogroup is Thomas Jefferson; his Y-chromosomal complement received prominence through the Sally Hemings controversy. Haplogroup K2-M70 has been detected in 7.2% of men (10 of 139 individuals) in a sample of modern Iraqis and 10.4% (21/201) of Somalis, which is much higher than its frequency in other populations.[1] K2-M70 individuals, at some later point, proceeded south to Africa. These chromosomes are seen in relatively high frequencies in Egypt, Oman, Tanzania, Ethiopia, and Morocco and are especially prominent in the Fulbe (18% [Scozzari et al. 1997, 1999]), the highest concentration of this haplogroup found so far."

According to an article by N. Al-Zahery et al., the potentially paraphyletic haplogroup K*-M9(xK2, O, P) occurs at a fairly high frequency among the modern population of Turkey. However, the loci of the downstream mutations that define Haplogroup L and Haplogroup N were not tested in this study, and other studies have suggested that these two haplogroups might comprise a substantial minority of the Y-chromosome diversity among modern Anatolian populations, so it is possible that most or all of the reported K*-M9 Y-chromosomes might actually belong to Haplogroup L or Haplogroup N.

Subgroups

The subclades of Haplogroup K with their defining mutation, according to the 2006 ISOGG tree (abbreviated for clarity to a maximum of five steps away from the root of Haplogroup K):

References

  1. Juan J Sanchez et al., "High frequencies of Y chromosome lineages characterized by E3b1, DYS19-11, DYS392-12 in Somali males," European Journal of Human Genetics (2005) 13, 856–866
  2. Laura Scheinfeldt, Françoise Friedlaender, Jonathan Friedlaender, Krista Latham, George Koki, Tatyana Karafet, Michael Hammer and Joseph Lorenz, "Unexpected NRY Chromosome Variation in Northern Island Melanesia," Molecular Biology and Evolution 2006 23(8):1628-1641
  3. Supplementary Table 2: NRY haplogroup distribution in Han populations, from the online supplementary material for the article by Bo Wen et al., "Genetic evidence supports demic diffusion of Han culture," Nature 431, 302-305 (16 September 2004)
  4. Table 1: Y-chromosome haplotype frequencies in 49 Eurasian populations, listed according to geographic region, from the article by R. Spencer Wells et al., "The Eurasian Heartland: A continental perspective on Y-chromosome diversity," Proceedings of the National Academy of Sciences of the United States of America (August 28, 2001)
  5. "Y-Chromosome Evidence for Differing Ancient Demographic Histories in the Americas," Maria-Catira Bortolini et al., American Journal of Human Genetics 73:524-539, 2003

External links

Template:Y-DNA

ca:Haplogrup K del cromosoma Y humà Template:WikiDoc Sources