Study on interactions between infectious diseases and host genetic factors in East Asia and Oceania

(1)在居住在泰国西北部的疟疾患者中，发现TNFA启动子多态性与脑型疟疾显著相关。此外，我们还检测到了几个与重症或脑型疟疾相关的HLA-DRB1和-B等位基因。(2)对东南亚和大洋洲疟疾流行地区间日疟原虫和诺氏疟原虫的受体Duffy抗原进行了分析。本研究中发现的Fya抗原与抗血清反应较弱。这种微弱的表型被认为在研究人群中保持了，因为对疟疾的抗药性具有选择性优势。(3)在泰国人群中调查了人类T淋巴细胞嗜T细胞病毒1型(HTLV-1)抗体的血清阳性率。虽然泰国位于HTLV-1流行国家之间，但未发现HTLV-1在泰国人群中流行。(4)研究了巴布亚新几内亚Gidra和Balopa人群的HLADRB1基因多态性。巴洛帕岛民的基因与美拉尼西亚的南岛人群体相似，也与非南岛人的吉德拉人相似，而他们与波利尼西亚人和密克罗尼西亚人的群体相距甚远。这一结果有力地表明，南岛人和非南岛人的混合存在于巴布亚新几内亚，无论他们使用的语言是什么。

(1) The significant association of TNFA promoter polymorphisms with cerebral malaria was found in malaria patients living in the northwest of Thailand. Also, we detected several HLA-DRB1 and -B alleles associated with severe or cerebral malaria. The TNFR2 polymorphism, 196M/R, was not associated with the disease severity in the malaria patients.(2) The Duffy antigen as a receptor for Plasmodium vivax and Plasmodium knowlesi was analyzed in the malaria-endemic regions of Southeast Asia and Oceania. The Fya-antigens found in this study showed weak reactivity to antisera. Such weak phenotypes are considered to have been maintained in the study populations due to a selective advantage through resistance to malaria.(3) Seroprevalence of antibodies to human T-lymphotropic virus type-1 (HTLV-1) was surveyed among the Thai population. Although Thailand is located between HTLV-1 harboring countries, HTLV-1 was found not to endemic in the Thai population.(4) HLA-DRB1 polymorphism was studied in the Gidra and Balopa populations of Papua New Guinea. The Balopa islanders showed a genetic similarity to Austronesian speaking groups in the Melanesia and also to the Gidra who are Non-Austronesian, while they are distant from the Polynesian and Micronesian populations. This result strongly suggests that the admixture between Austronesian and Non-Austronesian occurred in Papua New Guinea, regardless of their different language.