Showing posts with label Daic. Show all posts
Showing posts with label Daic. Show all posts

May 22, 2010

Origin of Gelong from Hainan island

Related: Portraits of ethnic groups of China including a portrait of Gelao, the mainland relatives of the Gelong and Li who are an indigenous group of Hainan.

Note that Hlai is the Li's own self-appellation. Wikipedia article on Kadai (Daic) languages. Note that haplogroup O1 has been linked to Daic languages, which would agree with the results on the Gelong people. Tai-Kadai people form their own autosomal cluster, demonstrated their common genetic origins.

J Hum Genet. doi:10.1038/jhg.2010.50.

Genetic origin of Kadai-speaking Gelong people on Hainan island viewed from Y chromosomes.

Li D, Sun Y, Lu Y, Mustavich LF, Ou C, Zhou Z, Li S, Jin L, Li H.

The government of China defined 56 official ethnicities for the ethnic groups in China for political purposes; however, there are many more than 56 ethnic groups. Therefore, similar groups must be pooled for registry, and the so-called ethnicity identification is an important official mission in China. Here, we showed how genetics can help in the ethnicity identification for the Gelong people on Hainan Island. The Gelong speak a Kadai language whose other speakers (officially of the Gelao ethnicity) are all far in the southwest of China. Being registered as a Han ethnicity, the Gelong lost all the benefits assigned to the minorities. Y-chromosome typing was performed in a sample of 78 individuals. Twenty single nucleotide polymorphisms (SNPs) and seven short tandem repeats (STRs) were typed and eight haplogroups were detected, among which haplogroup O1a(*) was the most dominant. Compared with the Y haplogroups of the populations in south China, the Gelong were found to be closest to the Gelao and the Hlai using principal components (PCs) analysis, dendrogram clustering and STR networks. The genetic similarity between the Gelong and the Hlai may have resulted from the gene flow during thousands of years of neighboring history on Hainan Island, whereas the similarity between the Gelong and the Gelao may have resulted from their common ancestry because there is less possibility of gene flow over such a far distance. As both linguistic and genetic evidence support the similarity between the Gelong and the Gelao, we suggest that the Gelong register as Gelao for their official ethnicity. However, this identification is invalid until it is accepted by the Gelong people themselves and the Hainan government.

Link

December 11, 2009

Mapping Human Genetic Diversity in Asia

From the press release:
Several genome-wide studies of human genetic diversity have been conducted on European populations. Now, for the first time, these studies have been extended to 73 Southeast Asian (SEA) and East Asian (EA) populations.

In a paper titled, "Mapping Human Genetic Diversity in Asia," published online Science on 10 Dec. 2009, over 90 scientists from the Human Genome Organisation's (HUGO's) Pan-Asian SNP Consortium report that their study conducted within and between the different populations in the Asia continent showed that genetic ancestry was highly correlated with ethnic and linguistic groups.

The scientists also reported a clear increase in genetic diversity from northern to southern latitudes. Their findings also suggest that there was one major inflow of human migration into Asia arising from Southeast Asia, rather than multiple inflows from both southern and northern routes as previously proposed. This indicates that Southeast Asia was the major geographic source of East Asian and North Asian populations.

(A figure illustrating the paper shows plausible routes of pre-historical migration of Asian human populations. According to the study, the PanAsia SNP Initiative, the most recent common ancestors of Asians arrived first in India and later, some of them migrated to Thailand, and South to the lands known today as Malaysia, Indonesia, and the Philippines. The first group of settlers must have gone very far south before they settled successfully. These included the Malay Negritos , Philippine Negritos , the East Indonesians, and early settlers of the Pacific Islands. Thereafter, one or several groups of people migrated North, mixed with previous settlers there and, finally, formed various populations we now refer to as Austronesian, Austro-Asiatic, Tai-Kadai, Hmong-Mien, and Altaic. The figure is titled, "Putative Pre-Historical Migration Routes of Asian Human Populations.")

The researchers noted that the geographical and linguistic basis of genetic subgroups in Asia clarifies the need for genetic stratification when conducting genetic and pharmacogenomic studies in this continent, and that human genetic mapping of Asia has important implications for the study of genetics and disease and for research to understand migratory patterns in human history.

HUGO President Edison Liu, M.D., who is Executive Director of the Genome Institute of Singapore (GIS), said, "This study was a milestone not only in the science that emerged, but the consortium that was formed. Ten Asian countries came together in the spirit of solidarity to understand how we were related as a people, and we finished with a truly Asian scientific community. We overcame shortage of funds and diverse operational constraints through partnerships, good will, and cultural sensitivity.

"Our next goal is to expand this collaboration to all of Asia including Central Asia and the Polynesian Islands," said Dr. Liu, one of the corresponding authors of the paper. "We also aim to be more detailed in our genomic analysis and plan to include structural variations, as well as over a million single nucleotide polymorphisms in the next analysis."

While HUGO initiated and coordinated the research, Dr. Liu pointed out, "Affymetrix, led by Dr. Giulia C. Kennedy and based in the US, is our primary technology partner in this endeavour. We greatly appreciate their support."
As usual for a Science paper there are voluminous (and free) supplementary materials. The Neighbor-Joining tree shows the clear correlation between linguistic affiliation and genetic identity of individuals.


UPDATE: As to the main thesis of the paper, namely that East Asians are descended from Southeast Asians rather than Central Asians, I have to say that I am not convinced. This thesis is based on two observations: minimum sharing between East Asians and Central/South Asians and south-north reduction of genetic diversity in East Eurasians. However, the high genetic diversity in Southeast Asians can be explained if they are taken to be old hybrids of Mongoloid northerners with "Australoid"-like southerners as physical anthropology suggests, and the seeming absence of influence of present-day Central/South Asians is due to the fact that the latter are largely Caucasoids of western Eurasian origin, and, thus, do not represent any putative ancestral populations to modern Mongoloids.

Science
doi:10.1126/science.1177074

Mapping Human Genetic Diversity in Asia

The HUGO Pan-Asian SNP Consortium

Abstract

Asia harbors substantial cultural and linguistic diversity, but the geographic structure of genetic variation across the continent remains enigmatic. Here we report a large-scale survey of autosomal variation from a broad geographic sample of Asian human populations. Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography. Most populations show relatedness within ethnic/linguistic groups, despite prevalent gene flow among populations. More than 90% of East Asian (EA) haplotypes could be found in either Southeast Asian (SEA) or Central-South Asian (CSA) populations and show clinal structure with haplotype diversity decreasing from south to north. Furthermore, 50% of EA haplotypes were found in SEA only and 5% were found in CSA only, indicating that SEA was a major geographic source of EA populations.

Link

July 14, 2008

Ancient mtDNA from Southeast Asia

American Journal of Physical Anthropology

Genetic history of Southeast Asian populations as revealed by ancient and modern human mitochondrial DNA analysis

Patcharee Lertrit et al.

Abstract

The 360 base-pair fragment in HVS-1 of the mitochondrial genome were determined from ancient human remains excavated at Noen U-loke and Ban Lum-Khao, two Bronze and Iron Age archaeological sites in Northeastern Thailand, radio-carbon dated to circa 3,500-1,500 years BP and 3,200-2,400 years BP, respectively. These two neighboring populations were parts of early agricultural communities prevailing in northeastern Thailand from the fourth millennium BP onwards. The nucleotide sequences of these ancient samples were compared with the sequences of modern samples from various ethnic populations of East and Southeast Asia, encompassing four major linguistic affiliations (Altaic, Sino-Tibetan, Tai-Kadai, and Austroasiatic), to investigate the genetic relationships and history among them. The two ancient samples were most closely related to each other, and next most closely related to the Chao-Bon, an Austroasiatic-speaking group living near the archaeological sites, suggesting that the genetic continuum may have persisted since prehistoric times in situ among the native, perhaps Austroasiatic-speaking population. Tai-Kadai groups formed close affinities among themselves, with a tendency to be more closely related to other Southeast Asian populations than to populations from further north. The Tai-Kadai groups were relatively distant from all groups that have presumably been in Southeast Asia for longer-that is, the two ancient groups and the Austroasiatic-speaking groups, with the exception of the Khmer group. This finding is compatible with the known history of the Thais: their late arrival in Southeast Asia from southern China after the 10th-11th century AD, followed by a period of subjugation under the Khmers.

Link

May 20, 2008

Paternal genetic affinity between western Austronesians and Daic populations

BMC Evol Biol. 2008 May 15;8(1):146.

Paternal genetic affinity between western Austronesians and Daic populations.

Li H, Wen B, Chen SJ, Su B, Pramoonjago P, Liu Y, Pan S, Qin Z, Liu W, Cheng X, Yang N, Li X, Tran D, Lu D, Hsu MT, Deka R, Marzuki S, Tan CC, Jin L.

ABSTRACT: BACKGROUND: Austronesian is a linguistic family spread in most areas of the Southeast Asia, the Pacific Ocean, and the Indian Ocean. Based on their linguistic similarity, this linguistic family included Malayo-Polynesians and Taiwan aborigines. The linguistic similarity also led to the controversial hypothesis that Taiwan is the homeland of all the Malayo-Polynesians, a hypothesis that has been debated by ethnologists, linguists, archaeologists, and geneticists. It is well accepted that the Eastern Austronesians (Micronesians and Polynesians) derived from the Western Austronesians (Island Southeast Asians and Taiwanese), and that the Daic populations on the mainland are supposed to be the headstream of all the Austronesian populations. RESULTS: In this report, we studied 20 SNPs and 7 STRs in the non-recombining region of the 1,509 Y chromosomes from 30 China Daic populations, 23 Indonesian and Vietnam Malayo-Polynesian populations, and 11 Taiwan aboriginal populations. These three groups show many resemblances in paternal lineages. Admixture analyses demonstrated that the Daic populations are hardly influenced by Han Chinese genetically, and that they make up the largest proportion of Indonesians. Most of the population samples contain a high frequency of haplogroup O1a-M119, which is nearly absent in other ethnic families. The STR network of haplogroup O1a* illustrated that Indonesian lineages did not derive from Taiwan aborigines as linguistic studies suggest, but from Daic populations. CONCLUSION: We show that, in contrast to the Taiwan homeland hypothesis, the Island Southeast Asians do not have a Taiwan origin based on their paternal lineages. Furthermore, we show that both Taiwan aborigines and Indonesians likely derived from the Daic populations based on their paternal lineages. These two populations seem to have evolved independently of each other. Our results indicate that a super-phylum, which includes Taiwan aborigines, Daic, and Malayo-Polynesians, is genetically educible.

Link

February 15, 2008

Pinghua Han Chinese are not of Han origin

An interesting study which demonstrates how a small subgroup of the Han Chinese, the Pinghua have a different origin than the rest of the Han. As in the case of some Finnish origin Russians, this illustrates that despite the general genetic coherence of ethnic groups, they can nonetheless include segments that were grafted onto their body. It is indeed the fact that ethnic groups constitute in a sense in many cases their own mini-races that allows us to identify outlier populations of different origins.

J Hum Genet. 2008 Feb 13 [Epub ahead of print]

Pinghua population as an exception of Han Chinese's coherent genetic structure.

Gan RJ et al.

The Han Chinese is the largest single ethnic group in the world, consisting of ten Chinese branches. With the exception of the Pinghua branch, the genetic structure of this group has been studied extensively, and Y chromosome and mitochondrial (mt)DNA data have demonstrated a coherent genetic structure of all Han Chinese. It is therefore believed that the Pinghua branch, being members of an old branch of the Han Chinese, despite being scattered in and around Guangxi Province where members of the Daic and Hmong-Mien are more prevalent than Han Chinese, is no exception. We have studied 470 individual samples (including 195 males) from Pinghua populations and other ethnic groups (Zhuang, Kam, Mulam, Laka, and Mien) from six areas (Hezhou, Fuchuan, Luocheng, Jinxiu, Sanjiang, and Wuxuan) in the north of the Guangxi Zhuang Autonomous Region of China. Both mtDNA and the Y chromosomes were typed in these samples. High frequencies of the Y chromosome haplogroups O2a* and O*, which always present at a high frequency among the populations of the southern minorities, were found in Pinghua populations. Only Pinghua populations in Luocheng and Jinxiu maintain the Han frequent haplogroup O3a5a. mtDNA lineages B4a, B5a, M*, F1a, M7b1, and N* were found in Pinghua populations, exhibiting a pattern similar to the neighboring indigenous populations, especially the Daic populations. Cluster analyses (dendrograms, principal component analyses, and networks) of Pinghua populations, the other Han branches, and other ethnic groups in East Asia indicated that Pinghua populations are much closer to the southern minorities than to the other Han branches. Admixture analyses confirmed this result. In conclusion, we argue that Pinghua populations did not descend from Han Chinese, but from southern minorities. The ancestral populations of Pinghua people were assimilated by the Han Chinese in terms of language, culture, and self-identification and, consequently, the Pinghua people became an exceptional branch of Han Chinese's coherent genetic structure.

Link

July 30, 2007

Ancient Chinese Y chromosomes

Another paper on ancient Y-DNA, it seems like the times where we could only expect to get mtDNA from prehistoric remains is coming to a close.

Hum Genet. 2007 Jul 27; [Epub ahead of print]

Y chromosomes of prehistoric people along the Yangtze River.
Li H et al.

The ability to extract mitochondrial and nuclear DNA from ancient remains has enabled the study of ancient DNA, a legitimate field for over 20 years now. Recently, Y chromosome genotyping has begun to be applied to ancient DNA. The Y chromosome haplogroup in East Asia has since caught the attention of molecular anthropologists, as it is one of the most ethnic-related genetic markers of the region. In this paper, the Y chromosome haplogroup of DNA from ancient East Asians was examined, in order to genetically link them to modern populations. Fifty-six human remains were sampled from five archaeological sites, primarily along the Yangtze River. Strict criteria were followed to eliminate potential contamination. Five SNPs from the Y chromosome were successfully amplified from most of the samples, with at least 62.5% of the samples belonging to the O haplogroup, similar to the frequency for modern East Asian populations. A high frequency of O1 was found in Liangzhu Culture sites around the mouth of the Yangtze River, linking this culture to modern Austronesian and Daic populations. A rare haplogroup, O3d, was found at the Daxi site in the middle reaches of the Yangtze River, indicating that the Daxi people might be the ancestors of modern Hmong-Mien populations, which show only small traces of O3d today. Noticeable genetic segregation was observed among the prehistoric cultures, demonstrating the genetic foundation of the multiple origins of the Chinese Civilization.

Link