The M214 mutation that defines Haplogroup NO occurred in a gamete of a man who belonged to Haplogroup K and who probably lived somewhere in Eurasia east of the Aral Sea about 35,000 to 40,000 years ago. This man has become the direct patrilineal ancestor of a very large percentage of present-day humans, as he is the forefather of both Haplogroup N and Haplogroup O, which together are overwhelmingly dominant throughout North and East Eurasia.
Distribution
Haplogroup NO*, which comprises all Y-chromosomes in the Haplogroup NO-M214 line that do not belong to either of the common descendant haplogroups N or O, is found extremely rarely among the males of modern human populations, with its highest reported sampled frequency being about 2.3%, or 6 of 259 individuals, in a sample of men from Japan.[1] The same study also reported finding Haplogroup NO* Y-chromosomes at even lower frequencies among males from Northeast Asia, Southeast Asia, and Central Asia. However, a comparison with other studies of Y-chromosome variation in the East Eurasian region shows that Haplogroup NO* Y-chromosomes have actually been found only among populations of Xinjiang in western China near the border with Afghanistan, Tajikistan, and Kyrgyzstan; among populations of Inner Mongolia that speak an Altaic language; among populations that reside in close proximity to the eastern edge of the Tibetan Plateau and speak a Tibeto-Burman language; and, of course, among populations of Japan. The general impression is that Haplogroup NO* patrilines persist at low but detectable frequencies on the (particularly western and northeastern) fringes of China or the greater Sinosphere. Nowhere do Haplogroup NO* Y-chromosomes comprise more than a tiny fraction of the total Y-chromosome diversity of any population.
The reason for the nearly complete extinction of Haplogroup NO* patrilines, in stark contrast with the preeminent success of Haplogroup NO-M214's other descendants, Haplogroup N in North Eurasia and Haplogroup O in East Eurasia, is unclear; however, this situation seems to be a good parallel to the near-extinction of Haplogroup P* patrilines in all regions except northern Central Asia despite the dominance of Haplogroup P's other descendants, Haplogroup R and Haplogroup Q, in West Eurasia and the Americas, respectively. It is likely that both repeated founder effects and strong genetic drift in small ancestral populations of Paleolithic hunter-gatherers are responsible for shaping the Y-chromosome distribution that is found in modern human populations.
Subgroups
The subclades of Haplogroup NO with their defining mutation, according to the 2008 ISOGG tree:
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