Haplogroup O (Y-DNA)

In human genetics, Haplogroup O (M175) is a Y-chromosome DNA haplogroup.

This haplogroup appears in 80-90% of all men in East and Southeast Asia, and it is almost exclusive to that region: M175 is almost nonexistent in Western Siberia, Western Asia, and Europe and is completely absent from Africa and the Americas, although certain clades of Haplogroup O do achieve significant frequencies among some tribal populations of South Asia, Altaic-speaking populations of Central Asia, and Austronesian-speaking populations of Oceania.

Haplogroup O is a descendant haplogroup of Haplogroup NO (M214), and is believed to have first appeared in Siberia or eastern Central Asia approximately 35,000 years ago. Haplogroup O shares a node in the phylogenetic tree of human Y-chromosomes with Haplogroup N, which is common throughout North Eurasia.

Among the subbranches of Haplogroup O are Haplogroup O1, Haplogroup O2, and Haplogroup O3. Haplogroup O* lineages, which belong to Haplogroup O but do not display any of the later mutations that define the major subclades O1, O2, and O3, can still be detected at a low frequency among most modern populations of Central Asia and East Asia. For example, a broad survey of Y-chromosome variation among populations of central Eurasia found haplogroup O-M175*(xO1a-M119,O2a-M95,O3-M122) in 2.5% (one out of 40 individuals) of a sample of Tajiks in Samarkand, 4.5% (1/22) of Crimean Tatars in Uzbekistan, 1.5% (1/68) of Uzbeks in Surkhandarya, 1.4% (1/70) of Uzbeks in Khorezm, 6.3% (1/16) of Tajiks in Dushanbe, 1.9% (1/54) of Kazakhs in Kazakhstan, 4.9% (2/41) of Uyghurs in Kazakhstan, and 31.1% (14/45) of Koreans. However, approximately 30% of all Korean O*(xO1a,O2a,O3) Y-chromosomes probably belong to Haplogroup O2b, which has been found to be very common among Koreans. There is also a possibility that the so-called Haplogroup O* Y-chromosomes that have been found among these populations might belong to Haplogroup O1*(xO1a-M119), Haplogroup O2*(xO2a-M95,O2b-M176), or Haplogroup O2b-M176.

Subgroups
The subclades of Haplogroup O with their defining mutation, according to the 2006 ISOGG tree:


 * O (M175)
 * O*
 * O1 (MSY2.2)
 * O1*
 * O1a (M119) Typical of Austronesians, southern Han Chinese, and Tai-Kadai peoples
 * O1a*
 * O1a1 (M101)
 * O1a2 (M50, M103, M110)
 * O2 (P31, M268)
 * O2*
 * O2a (M95) Typical of Austro-Asiatic peoples, Tai-Kadai peoples, Malays, and Indonesians, with a moderate distribution throughout South Asia, Southeast Asia, East Asia, and Central Asia
 * O2a*
 * O2a1 (M88, M111) Frequently found among Hani, Tai peoples, Cambodians, and Vietnamese, with a moderate distribution among Qiang, Yi, Hlai, Yao, Taiwanese aborigines, and Han Chinese of Sichuan, Guangxi, and Guangdong
 * O2a1*
 * O2a1a (PK4) Found at low frequency among Pashtuns
 * O2a2 (M297)
 * O2b (SRY465 (M176))
 * O2b*
 * O2b1 (P49) Typical of Koreans
 * O2b1*
 * O2b1a (47z) Typical of Japanese and Ryukyuans
 * O3 (M122) Typical of populations of East Asia, Southeast Asia, and culturally Austronesian regions of Oceania, with a moderate distribution in Central Asia
 * O3*
 * O3a (M324)
 * O3a*
 * O3a1 (M121, DYS257)
 * O3a2 (M164)
 * O3a3 (LINE1, M159) Found at low to moderate frequency throughout East Asia and Southeast Asia, especially among Hmong-Mien peoples and Han Chinese
 * O3a4 (M7) Typical of Hmong-Mien peoples
 * O3a4*
 * O3a4a (M113, M188, M209)
 * O3a4a*
 * O3a4a1 (N4)
 * O3a4a2 (N5)
 * O3a5 (M134) Typical of Sino-Tibetan peoples, with a moderate distribution throughout East Asia and Southeast Asia
 * O3a5*
 * O3a5a (M117, M133) Typical of Han Chinese and Tibetans, with a moderate distribution throughout East Asia
 * O3a5a*
 * O3a5a1 (M162)
 * O3a5b (P101)
 * O3a6 (M300)
 * O3a7 (M333)