Differences in platelet indices between healthy Han population and Tibetans in China.

INTRODUCTION: The present data on the evaluation of platelet (PLT) parameters in Chinese Han population and Tibetans are still limited. The objective of this study was to determine the differences in common PLT indices between Han population and Tibetans in China, through a large-scale investigation of healthy people. METHODS: 2131 Han people from Chengdu Plain, 1099 Tibetans from Qinghai-Tibet Plateau and 956 Plateau Han migrants were included in this study. All the subjects were healthy people through the health screening. PLT indices were measured with Sysmex XE-2100 and XT-1800i blood cell automatic analyzer. RESULTS: Compared with Han people in Chendu Plain, Tibetans had higher PLT count (P<0.01) but lower mean platelet volume (MPV), platelet distribution width (PDW) and platelet-large cell ratio (P-LCR) (P<0.01); while Plateau Han migrants had lower PLT count, MPV and P-LCR (P<0.05). When compared with Tibetans, Plateau Han migrants had lower levels of mean PLT count but higher PDW and P-LCR (P<0.05). CONCLUSIONS: There are ethnic differences in PLT indices between Chinese Han population and Tibetans. Based on this finding, it would be reasonable to conduct formal prospective studies to determine the clinical significance of these differences and to explore the effects of genetic background on these indices.

Frequency distribution of single nucleotide polymorphisms in P-selectin gene in Chinese Tibetan and Han populations.

BACKGROUND: Chinese Tibetans have a series of distinctive physiological traits which enable them to tolerate the extreme environment of the Tibetan plateau. P-selectin gene has been proved to be highly polymorphic in Europeans and Americans. Nevertheless, studies on either the frequency distributions of single nucleotide polymorphisms (SNPs) or haplotype diversity and linkage disequilibrium of P-selectin gene in Chinese Tibetan population are still unavailable. METHODS: The frequency distributions of 3 SNPs in P-selectin gene promoter (-2123C/G, -1969A/G, -1817T/C) and 3 SNPs in exon region (Ser290Asn, Val599Leu, Thr715Pro) were investigated by real-time PCR and high-resolution melting method among 314 Chinese Tibetans and 328 age- and sex-matched Han people. RESULTS: The frequencies of the -2123G and -1817T alleles among the Tibetan population had no significant differences from those of the Han population. Among the Tibetan population, the G allele frequency of -1969A/G and Ser290Asn were both higher than those of the Han population. Val599Leu and Thr715Pro did not show any polymorphism in the two populations. In the Tibetan population, -2123C/G, -1969A/G, -1817T/C and Ser290Asn were in tight linkage disequilibrium with each other. CONCLUSIONS: The frequency distributions of -1969A/G and Ser290Asn polymorphisms in the Tibetan population were different from those in the Han population.