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The greater Himalayan region demarcates two of the most prominent linguistic phyla in Asia: Tibeto-Burman and Indo-European. Previous genetic surveys, mainly using Y-chromosome polymorphisms and/or mitochondrial DNA polymorphisms suggested a substantially reduced geneflow between populations belonging to these two phyla. These studies, however, have mainly focussed on populations residing far to the north and/or south of this mountain range, and have not been able to study geneflow patterns within the greater Himalayan region itself. We now report a detailed, linguistically informed, genetic survey of Tibeto-Burman and Indo-European speakers from the Himalayan countries Nepal and Bhutan based on autosomal microsatellite markers and compare these populations with surrounding regions. The genetic differentiation between populations within the Himalayas seems to be much higher than between populations in the neighbouring countries. We also observe a remarkable genetic differentiation between the Tibeto-Burman speaking populations on the one hand and Indo-European speaking populations on the other, suggesting that language and geography have played an equally large role in defining the genetic composition of present-day populations within the Himalayas.

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive disease initially reported by Bardet and Biedl in the 1920s. BBS is a pleiotropic and genetically heterogeneous disorder characterized by retinopathy, obesity, polydactyly, renal malformations and functional abnormalities, learning disabilities and hypogenitalism. BBS patients are also prone to diabetes mellitus, hypertension and congenital heart disease. To date, 16 BBS genes (BBS1-BBS16) have been identified. However, the molecular etiology of BBS is not yet entirely clear. In this article, we have reviewed recent research on BBS and discussed its implications for understanding of ciliopathology.

To investigate the characteristics of rhesus monkey embryonic stem cells and to promote their clinical application, the differentiation and proliferation of rosettes neural stem cells from GFP marked rhesus monkey embryonic stem cells were studied The results showed that: 1) A stable and high-efficient neural differentiation system was established. More than 95% of the embryonic stem cells were differentiated into neural stem cells on the 12(th) days of differentiation; 2) the rosettes neural stem cells differentiated from the rhesus monkey embryonic stem cells could maintain their rosettes-shape by proliferating with bFGF/EGF; 3) the neural stem cells could differentiate into neurons after transplanted into the rhesus monkey brain. In conclusion, the rosettes neural stem cells differentiated from rhesus monkey embryonic stem cells could maintain their characteristics after proliferation with bFGF/EGF and they could survive and differentiate into neurons after transplanted into the rhesus monkey brain, which strongly supports the clinical application of neural stem cells in the future.

The aim of this study was to investigate the susceptibility and prognostic implications of the cyclin D1 gene (CCND1) G870A polymorphism to nasopharyngeal carcinomas (NPC) in Han population in Yunnan China.Two hundred and forty one cases with NPC and 271 matched cancer-free controls were genotyped for the CCND1 G870A polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequencing. The adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated by using unconditional logistic regression model. Overall survival was assessed using univariate and multivariate analyses.Contrast with homozygous CCND1 G870G, A allele significantly increasing risk of NPC was associated with homozygous A870A (OR = 4.79, 95% CI 2.77 - 8.28, P0.001) and heterozygous A870G (OR = 1.72, 95% CI 1.10 - 2.68, P = 0.017). The subjects at least having one CCND1 870A allele had OR of 2.40 (95% CI 1.59 - 3.63, P0.001). Furthermore, smoking may increase the risk of developing NPC interacting with CCND1 G870A polymorphism. Kaplan-Meier analysis and Cox regression analysis demonstrated that the five-year survival rate of subjects with AA, AG and GG genotype was 56.2%, 78.5% and 81.4% (AA vs GG, P = 0.003; AA vs AG, P = 0.012; AG vs GG, P = 0.132), but not independent prognostic factor in NPC (P = 0.501).The CCND1 870A allele is associated with the NPC in Han population in Yunnan China, meanwhile, showed a significant prognosis for those patients.

In the same ethnic group, people residing at different places may have genetic difference. The difference can be the results of migration and admixture events happened in history. To clarify the genetic relationship and micro-evolution of two Bai ethnic populations residing in Yunnan and Hunan province respectively,we investigated their genetic difference from paternal and maternal genealogy with six other ethnic groups as outgroups. Fourteen loci from mtDNA and thirteen loci from Y chromosome were selected for genotyping using PCR-RFLP methods. Result showed that H6 and H8 are the same dominant Y chromosome haplotypes in two Bai groups. However,the distribution of mtDNA haplogroups showed difference between two Bai populations. D, B, M8 are the predominant haplogroups in Hunan Bai ethnic population, whereas M, G, F are dominant in Yunnan Bai ethnic population. Principal Component (PC) analysis based on the Y chromosome haplotypes showed that two Bai ethic populations cluster together. It shows a close paternal genetic relationship between two Bai ethnic populations. From the mtDNA PC plot, it is clear that Hunan Bai is close to Hunan Han and Tujia, whereas Yunnan Bai is close to ethnic groups living in Yunnan province. The difference of mtDNA haplogroup distribution in two Bai people may reflect the maternal gene flow between ethnic groups living in Hunan province after the ancestors of Hunan Bai migrated from Yunnan province to Hunan province 800 years ago.

The genetic polymorphism of mitochondrial DNA in the coding region in 16 ethnic populations of Yunnan was analyzed using PCR-RFLP in a total of 654 samples. Seventeen haplogroups were found, four of which were undefined haplogroups. Haplogroup distribution and Principal Component (PC) analysis showed that the ethnic groups descended from Bai-Yue tribe have B, F and M7 as the predominant haplogroups,which indicated their origination from southern China. Haplogroup A, D and N9 were predominant in the Mongolian ethnic group, reflecting their north-originated characteristics. The groups descended from Di-Qiang tribe shared the predominant haplogroups with both the south and north originated groups,which demonstrated that they inherit the maternal characteristics from both southern and northern populations. There is genetic difference among the populations in the same ethnic group and is usually smaller than that among the ethnic groups from different ancient tribes, but not necessarily smaller than that among the groups from the same tribe.

Based on the historical records, 18 of the 26 ethnic groups in Yunnan Province are the descendant populations of three ancient tribes, Bai-Yue, Bai-Pu and Di-Qiang, linguistically belonging to the Daic, Austro-Asiatic and Tibeto-Burman, respectively. In order to trace the origins of these native ethnic groups, a total of 13 East Asian specific Y-chromosome biallelic markers were used to study the genetic structure of 20 local populations covering all the 18 ethnic groups in Yunnan Province. Haplotypes were analysis by PCR-RFLP method. Our results showed that H11 and H12 were the predominant haplotypes in the descendant populations of Bai-Yue tribe. H5, H6 and H8 were the dominant haplotypes in Di-Qiang descendants, and the frequencies of H6, H8 and H11 were very high in the descendant populations of Bai-Pu. To investigate relationships among 20 populations, a three dimensional PC analysis were performed based on the distribution of the 13 haplotypes. All populations were divided into two clusters in the PC plot. The first cluster was mainly composed by the descendant populations of Bai-Yue, and the second one was mainly composed by the descendants of Di-Qiang tribe. This result indicated that Bai-Yue and Di-Qiang's paternal lineage had different origins, which was in agreement with the historical documents and linguistic classification.

To study the frequency distribution of flavin-containing monooxygenase 3 (FMO3) mutant alleles in 28 populations originating from 24 ethnic minorities in Yunnan of China.FMO3 genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism.The average frequencies of FMO3/Stop(148), FMO3/Lys(158) and FMO3/Gly(308) were 0.395(0.174-0.803), 0.208 (0.056-0.414), 0.046(0-0.217), respectively. The frequencies of FMO3/Gly(308) in Blang, Huayaodai, Shuidai, Zhuang, De'ang, Jingpo, Nu and Hui populations were null.It was found that the frequencies of FMO3 mutant alleles varied not only in different ethnic groups, but also in different populations that stemmed from the same ethnic group.

To investigate the gene frequencies of 4 STR loci in Tibetan population of Yunnan.Multiple polymerase chain reaction (PCR), denaturing polyacrylamide gel electrophoresis and silver staining were used to detect D21S11, D8S1179, D16S539 and LPL loci. DNA samples collected from 105 unrelated Tibetan individuals in Yunnan province were analyzed.At D21S11, D8S1179, D16S539 and LPL loci, 13, 8, 7, 6 alleles and 33, 21, 16 and 9 genotypes were observed, respectively. The genotype distribution of the 4 STR was in accordance with the Hardy-Weinberg equilibrium.The high combined discrimination power and exclusion power of the four loci in Tibetan population make multi-PCR detection a valuable tool for forensic identity, genetics and anthropology.

To investigate the frequencies distribution of GSTT1 and GSTM1 null genotypes in 24 Yunnan populations.GSTT1 and GSTM1 genotypes were analyzed by PCR procedure.The range of frequencies for GSTT1 and GSTM1 null genotypes in the populations were 0.188-0.633 and 0.400-0.745, respectively, and in the districts were 0.286-0.583, 0.433-0.745 respectively. There was significant relationship between GSTT1 frequencies and populations.The frequencies of GSTT1 and GSTM1 null genotypes in 24 Yunnan populations were different, but they were almost the same in different districts of Yunnan.

To investigate the feasibility of DNA analysis from free margin of the nail, genomic DNA was extracted from the free margin of nail clipping of 10 volunteers using the proteinase K/SDS -based organic method, the Chelex-100 method, or a combined method. Target DNA was simultaneously amplified using a fluorescent multiplex AmpFlSTR Identifier kit. The PCR products were analyzed on the ABI PRISM 3130 Genetic Analyzer. The results showed that, compared with profiles achieved by genotyping of blood samples from each volunteer as reference, 100% concordance was achieved using the combined method. The STR genotype profiles obtained through the organic method were acceptable, despite preferential amplification at some loci. In contrast, no readable profiles could be determined when DNA was extracted by the Chelex-100 method, and there were a large number of alleles missing. Our data suggest that free margin of nail can be used for nuclear DNA analysis, but the type of DNA isolation method used is critical. The traditional organic extraction method works reasonably well for free margin nail DNA isolation, and combination of organic extraction and the Chelex-100 method works best.

The tumor suppressor p53 is a master sensor of stress. Two human-specific polymorphisms, p53 codon 72 and MDM2 SNP309, influence the activities of p53. There is a tight association between cold winter temperature and p53 Arg72 and between low UV intensity and MDM2 SNP309 G/G in a cohort of 4029 individuals across Eastern Asia that suggests causative selection. Moreover, the two polymorphisms are not coselected. Haplotype-based selection analysis further suggests that this is a striking example of two functional polymorphisms being strongly selected for in human populations in response to environmental stresses.