Anthro-genetics on Paleomongoloid in Pan-Pacific and Northland Areas

人类t细胞白血病病毒1型（htlv - 1）正以高流行的微地理聚集性传播到世界各地。世界蒙古人种HTLV流行病学证据表明，HTLV- 1在日本南部和南美洲安第斯地区高度流行。另一方面，HTLV 2型（HTLV- ii）广泛分布于除安第斯山脉外的整个南美洲。两种携带者的HLA单倍型是互异的，即安第斯HTLV-I型携带者的HLA单倍型在日本人中普遍存在，而HTLV-II型携带者的HLA单倍型在北美印第安人中普遍存在。这表明HLA单倍型可能在南美土著人中存在种族分离，并且可能与htlv - 1和htlv - 2感染的遗传易感性有关。在该项目的先前研究中，从1500年前的安第斯木乃伊中检测到前病毒HTLV-I的基因片段。这一观察结果表明，htlv - 1可能在土著安第斯人从亚洲大陆迁移到安第斯山脉定居之前至少存在了1000年。在中国藏族人群中，乙型肝炎病毒（HBV）基因型迄今尚未得到研究。全球分布的HBV分为7个基因型，按地理位置划分为A到G。由于藏东、藏西地区藏族分离人群HBV感染率较高，采用血浆DNA pcr -微孔板杂交法检测HBV基因型。我们只检测到藏人HBV的基因型，这种基因型C已知是亚洲蒙古人种中主要的HBV类型，特别是在泰国和韩国。这些结果表明，西藏村民没有暴露于HTLV-I，但高度感染HBV，特别是基因型C。HBV和HLA基因序列值得进一步研究。

Human T-cell leukemia virus type 1 (HTLV-l) is spreading throughout the world with microgeographical clusters of hyperendemicity. Epidemiologic evidences on HTLV among Mongoloids in the world showed that HTLV-l is highly endemic in South Japan and in the Andes district of South America. In the other hand HTLV type 2 (HTLV-II) is broadly distributed in the whole South America except the Andes line. The HLA haplotypes of these two carriers were mutually exclusive, i.e., the HLA haplotypes of Andes HTLV-I carriers were common among Japanese while those of HTLV-II carriers were prevalent among North American Indians. This suggested that HLA haplotypes might be ethnically segregated among South American natives and might be involved in the genetic susceptibility to HTLV-I and HTLV-II infections. In a previous study in this program, gene fractions of proviral HTLV-I from Andean mummy aged 1500 years was detected. This observation suggested that HTLV-I may have existed at least 1000 years before aboriginal Andean migrated from the Asian Continent and settled down in the Andes.In Tibetan populations in China, the hepatitis B virus (HBV) genotypes have not yet been studied up until now. HBV distributed in the world is classified into seven genotypes, designated as A to G, geographically separated. Since the prevalence of HBV infection in isolated Tibetan people in the east and west regions of Tibet was very high, the HBV genotypes were determined by PCR-microwell plate hybridization method using plasma DNA. We detected only genotype in Tibetan HBV This genotype C is known to be a predominant type of HBV among Asian Mongoloids, especially in Thailand and Korea These results revealed that the Tibetan villagers are not exposed by HTLV-I but highly infected with HBV, especially with genotype C. HBV and HLA gene sequences warrant further investigation in this context.