Yongli Dong

Y-Chromosome Evidence of Southern Origin of the East Asian–Specific Haplogroup O3-M122

The prehistoric peopling of East Asia by modern humans remains controversial with respect to early population migrations. Here, we present a systematic sampling and genetic screening of an East Asian-specific Y-chromosome haplogroup (O3-M122) in 2,332 individuals from diverse East Asian populations. Our results indicate that the O3-M122 lineage is dominant in East Asian populations, with an average frequency of 44.3%. The microsatellite data show that the O3-M122 haplotypes in southern East Asia are more diverse than those in northern East Asia, suggesting a southern origin of the O3-M122 mutation. It was estimated that the early northward migration of the O3-M122 lineages in East Asia occurred approximately 25,000-30,000 years ago, consistent with the fossil records of modern humans in East Asia.

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

BackgroundThe 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.ResultsIn 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.ConclusionWe 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.

Relationship between the CAG Repeat Polymorphism in the Androgen Receptor Gene and Acne in the Han Ethnic Group

Background: The modulatory domain of the human androgen receptor (AR) gene contains a polymorphic CAG repeat coding for a polyglutamine tract which is inversely correlated with transcriptional activity of the AR. Androgens acting through the AR play a crucial role in the pathogenesis of acne vulgaris. We therefore investigated the relationship between CAG repeat polymorphism in the AR gene and acne susceptibility. Methods: 206 acne patients and 200 controls participated in the study. Genomic DNA was extracted from peripheral blood lymphocytes of individual patients, and the CAG repeat region was amplified by polymerase chain reaction (PCR) using fluorescence-labeled primers. Samples were then run on an ABI 377 gene scan analysis gel with an internal molecular-weight marker. Ten male samples were chosen randomly for sequencing to confirm the number of CAG repeats. The 2-sample independent t test was used to analyze the data. Results: The mean number of the CAG repeat in the AR was 22.07 (14–28) in the controls and 20.61 (13–26) in the male acne group. There was a significant correlation between the CAG repeat length and male acne. No significant difference was observed between female patients and their controls. Conclusion: The results suggest that the AR gene CAG repeat polymorphism may be one of the candidate genetic markers for male acne susceptibility in the Han population.

The Relationship between CYP17 –34T/C Polymorphism and Acne in Chinese Subjects Revealed by Sequencing

Background: Although many arguments have been raised on the role of heredity in the etiology of acne, the relevant genetic elements in the pathogenesis of the disease are not well established. Objective: The aim of our study was to evaluate the association between a genetic polymorphism in the promoter region of the CYP17 gene and the development of acne. Methods: 206 acne patients and 200 controls were included in the study. A polymerase chain reaction (PCR) sequencing technique was used to reveal a CYP17 gene polymorphism in its promoter region. A χ2 test was used for data analysis. Results: CYP17 –34T/C polymorphism was found and the frequency distribution of the C/C homozygotes and C allele in the male patients with severe acne (33.3 and 60.9%, respectively) were statistically significantly different from those of the control samples (18.2 and 46.6%; p < 0.05). No significant difference was observed between the female patients, mild + moderate male patients and their controls, respectively. Conclusion: The CYP17 –34C/C homozygote Chinese men are at a significantly increased risk of developing severe acne.

Gene admixture in ethnic populations in upper part of Silk Road revealed by mtDNA polymorphism

To evaluate the gene admixture on the current genetic landscape in Gansu Corridor (GC) in China, the upper part of the ancient Silk Road which connects the Eastern and Central Asia, we examined mitochondrial DNA (mtDNA) polymorphisms of five ethnic populations in this study. Using PCR-RFLP and sequencing, we analyzed mtDNA haplotypes in 242 unrelated samples in three ethnic populations from the GC region and two ethnic populations from the adjacent Xinjiang Uygur Autonomous Region of China. We analyzed the data in comparison with the previously reported data from Eastern, Central and Western Asia and Europe. We found that both European-specific haplogroups and Eastern Asian-specific haplogroups exist in the Gansu Corridor populations, while a modest matrilineal gene flow from Europeans to this region was revealed. The Gansu Corridor populations are genetically located between Eastern Asians and Central Asians, both of who contributed significantly to the maternal lineages of the GC populations. This study made the landscape of the gene flow and admixture along the Silk Road from Europe, through Central Asia, to the upper part of the Silk Road more complete.

Genetic imprint of the Mongol: signal from phylogeographic analysis of mitochondrial DNA

AbstractMitochondrial deoxyribonucleic acid (DNA) from 201 unrelated Mongolian individuals in the three different regions was analyzed. The Mongolians took the dominant East Asian-specific haplogroups, and some European-prevalent haplogroups were detected. The East Asians-specific haplogroups distributed from east to west in decreasing frequencies, and the European-specific haplogroups distributed conversely. These genetic data suggest that the Mongolian empire played an important role in the maternal genetic admixture across Mongolians and even Central Asian populations, whereas the Silk Road might have contributed little in the admixture between the East Asians and the Europeans.

Y-chromosome distributions among populations in Northwest China identify significant contribution from Central Asian pastoralists and lesser influence of western Eurasians

Correction to: Journal of Human Genetics (2010) 55, 314–322; doi:10.1038/jhg.2010.30; published online 23 April 2010 A typo in the above article was noticed after its publication. In the following sentence from the Materials and methods section of the original article, the second ‘DYS392’ with underline is a typo.

Polymorphism of the DPB1 locus in Hani ethnic group of south-western China.

Polymorphism of HLA‐DPB1 was revealed with a sequencing‐based typing (SBT) method in 47 unrelated healthy individuals from Yunnan Hani ethnic minority. The alleles DPB1*5901 and DPB1*7001 were detected for the first time in Chinese populations. A dendrogram showed that the Hani ethnic group belongs to the southern group of Chinese.

The distribution of Y chromosome haplogroups in the nationalities from Yunnan Province of China

The genetic structure of 26 identified nationalities from Yunnan Province of China was studied using Y chromosome haplogroups. A total of 12 haplogroups were obtained in 1214 male samples from all the nationalities. The genetic relationships among 26 nationalities were studied. The ethnic groups were compared according to their different ancient lineages. The ancient lineages had their own characteristics in the distribution of Y chromosome haplogroups. Our results showed that Yunnan Province has great genetic diversity in its people. The ethnic groups differ from each other in the number of haplogroups and haplogroup frequencies. The genetic evidence was in agreement with the study of linguistic and historical records.

Y-STR polymorphisms among five Chinese minorities, Mosuo, Mongolian, Naxi, Pumi and Tibetan, in Yunnan Province, PR China.

Two hundred and thirty samples from five minority populations resident in Yunnan Province, PR China (the Mosuo, Mongolian, Naxi, Pumi and Tibetan communities) were analysed at eight polymorphic Y chromosome short tandem repeats (Y-STRs) loci. A total of 59 alleles were identified, with the largest number (n = 44) in the matriarchal Mosuo community. Two or three Y alleles were specific to each population. One hundred and thirty-five haplotypes were constructed, with 45 haplotypes in Tibetans, 34 in the Mosuo, 29 in Mongolians, 26 in the Pumi and 17 in the Naxi. The Tibetan and Mosuo peoples were closest in the neighbour-joining tree, whereas the Mongolians differed from the other four populations, reflecting their origins and present-day geographical location in Yunnan.