Friday, October 31, 2008

Asian migrations as indicated by Y chromosome YAP+ haplogroup

The following two abstracts of article deal with Y chromosome haplogroup D, a type of the YAP+ haplogroups found in Africa and Asia. Most YAP+ haplogroups are found in Africa with the exception of haplogroup D.

The first study suggests that Japanese and Tibetan populations are made up of two primary waves of male ancestors as indicated by Y chromosome types. The D haplogroup apparently spread out over much of East Asia at an early date from more southern parts of Asia, and then was displaced later primarily from migrations of peoples among whom the O haplogroup was dominant. These latter peoples also migrated from the South to the North. In Japan, YAP+ is most frequently found among the Ainu people of Hokkaido.

In the second study, frequencies of YAP+ carriers in Yunnan, a southwestern province of China, are given. The Primi (Pumi), a Tibeto-Burmese-speaking group, has the highest frequency (72.3%) of YAP+ not only in Yunnan but throughout eastern Asia.

The scattered distribution of YAP+ in Asia resembles that of another marker, haplogroup C, which however, is oriented more toward the Pacific islands.

Y chromosome evidence of earliest modern human settlement in East Asia and multiple origins of Tibetan and Japanese populations

Authors: Hong Shi, Hua Zhong, Yi Peng, Yong-li Dong, Xue-bin Qi, Feng
Zhang, Lu-fang Liu, Si-jie Tan, Run-lin Ma, Chun-jie Xiao, Spencer
Wells, Li Jin and Bing Su
BMC Biology 2008, 6:45

The phylogeography of the Y chromosome in Asia previously suggested
that modern humans of African origin initially settled in mainland
southern East Asia, and about 25,000-30,000 years ago, migrated
northward, spreading throughout East Asia. However, the fragmented
distribution of one East Asian specific Y chromosome lineage (D-M174),
which is found at high frequencies only in Tibet, Japan and the
Andaman Islands, is inconsistent with this scenario.

Results: In this study, we collected more than 5,000 male samples from
73 East Asian populations and reconstructed the phylogeography of the
D-M174 lineage. Our results suggest that D-M174 represents an
extremely ancient lineage of modern humans in East Asia, and a deep
divergence was observed between northern and southern populations.

Conclusions: We proposed that D-M174 has a southern origin and its
northward expansion occurred about 60,000 years ago, predating the
northward migration of other major East Asian lineages. The Neolithic
expansion of Han culture and the last glacial maximum are likely the
key factors leading to the current relic distribution of D-M174 in
East Asia.

The Tibetan and Japanese populations are the admixture of two ancient
populations represented by two major East Asian specific Y chromosome
lineages, the O and D haplogroups.


The geographic polymorphisms of Y chromosome at YAP locus among 25 ethnic groups in Yunnan, China.

Shi H, Dong Y, Li W, Yang J, Li K, Zan R, Xiao C.

Human Genetics Center of Yunnan University, 650091, Kunming, China.

The genetic polymorphisms of Y chromosome at YAP locus in 25 ethnic groups (33 populations) of China were analyzed in a total of 1294 samples. The average YAP+ frequency of the 33 populations was 9.2%, coinciding with published data of Chinese populations. Primi has the highest YAP+ frequency (72.3%), which is also the highest YAP+ among all the eastern Asian populations studied. The YAP+ occurred in 17 populations studied including Tibetan (36.0%), Naxi (37.5% and 25.5%), Zhuang (21.3%), Jingpo (12.5%), Miao (11.8%), Dai (11.4%, 10.0%, 3.3% and 2.0%), Yi (8.0%), Bai of Yunnan (6.7% and 6.0%), Mongol of Inner Mongolia (4.3%), Tujia of Hunan (2.6%), Yao (2.2%) and Nu (1.8%). The other 15 populations are YAP-including Lahu (2 populations), Hani, Achang, Drung, Lisu, Sui, Bouyei, Va, Bulang, Deang, Man and Hui and Mongol of Yunnan and Bai of Hunan. The YAP+ frequencies varied among the different ethnic groups studied, and even different among the same ethnic group living in different geographic locations. Using the genetic information, combined with the knowledge of ethnology, history and archaeology, the origin and prehistoric migrations of the ethnic groups in China, especially in Yunnan Province were discussed.