Yang Hsin-Chou, Lin Chien-Hsin, Hsu Chia-Ling, Hung Shuen-Iu, Wu Jer-Yuan, Pan Wen-Harn, Chen Yuan-Tsong, Fann Cathy S J
Academia Sinica, Institute of Biomedical Sciences, 128 Academia Road, Section 2 Nankang, Taipei 115, Taiwan, ROC.
J Biomed Sci. 2006 Jul;13(4):489-98. doi: 10.1007/s11373-006-9077-7. Epub 2006 Mar 17.
Genetic dissection of complex diseases is both important and challenging. The human major histocompatibility complex is involved in many human diseases and genetic mechanisms. This highly polymorphic chromosome region has been extensively studied in Caucasians but not as well in Asians. Thus, we compared genotypic distributions, linkage disequilibria and haplotype blocks between Caucasian and Taiwan's Han Chinese populations. Moreover, we investigated the population admixture and phylogenetic system in Han Chinese residing in Taiwan. The results show that Taiwan's Han Chinese differ drastically in genotypic information compared with Caucasians but are relatively homogeneous among the three major ethnic subgroups, Minnan, Hakka and Mainlanders. Differences in allele frequency (AF) between Taiwanese and Caucasians in some disease-associated loci may reveal clues to differences in disease prevalence. The results of ethnic heterogeneity imply that public databases should be used with caution in cases where the study population(s) differs from the population characterized in the database. The high homogeneity we observed among the Taiwanese subpopulations mitigates the possibility of spurious association caused by ignoring population stratification in Taiwanese disease gene association studies. These results are useful for understanding our genetic background and designing future disease gene mapping studies.
复杂疾病的基因剖析既重要又具有挑战性。人类主要组织相容性复合体参与了许多人类疾病和遗传机制。这个高度多态的染色体区域在高加索人群中已得到广泛研究，但在亚洲人群中的研究较少。因此，我们比较了高加索人群和台湾汉族人群之间的基因型分布、连锁不平衡和单倍型块。此外，我们还研究了居住在台湾的汉族人群的群体混合情况和系统发育体系。结果表明，台湾汉族人群与高加索人群在基因型信息上存在显著差异，但在闽南、客家和大陆三个主要族群中相对同质。台湾人群与高加索人群在某些疾病相关位点的等位基因频率差异可能揭示疾病患病率差异的线索。族群异质性的结果表明，当研究人群与数据库中所描述的人群不同时，应谨慎使用公共数据库。我们在台湾亚人群中观察到的高度同质性降低了台湾疾病基因关联研究中因忽视群体分层而导致虚假关联的可能性。这些结果有助于了解我们的遗传背景，并为未来的疾病基因定位研究提供设计依据。
