We have analyzed HLA haplotypes in Japanese, using high resolution allele typing for 8 loci of HLA-A,-C,-B,DRB1,-DRB345,-DQA1,-DQB1,-DPB1. It is a purpose to identify linkages between alleles unidentified by the serologicalumethod such as A*0201 or A*0206 and those of other loci. We presented the data of haplotypes inclading alleles with comparatively low frequency. Unique linkage disequilibria were recognized in A2, A26, B13, B44, B61, B62, B39 and C locus with serologically “blank” alleles in the class I region. Tight linkages between DR-DQ were confirmed in the HLA class II region, weaker but significant linkages to DPB1 were also recognized.

To examine the nature of the peptides bound to HLA-DR molecules of T cells we isolated HLA-DR molecules from MT2, a human T cell lymphotropic virus-1 infected T cell line, and determined the amino acid sequence of the peptides eluted from the HLA-DR molecules. We then confirmed the binding capacity of the peptides, synthesized on the basis of the amino acid sequence obtained above, to HLA-DR transfected L cells.

Central Asia is a vast region at the crossroads of different habitats, cultures, and trade routes. Little is known about the genetics and the history of the populations of this region. In order to investigate the genetic characteristics of Kyrgyz and their affinities to other populations, HLA-DRBI polymorphism was investigated in 148 healthy unrelated individuals living in Kyrgyz Republic. Kyrgyz, as representative of the Central Asian cluster, not only contain a considerable admixture of Mongoloid genes, but also Caucasian genes as well. The predominant HLA-DRB 1 alleles were HLA-DRB 1 *0701 and *0301 . Genetic distances and principal component analysis based on DRB 1 allele frequencies suggested that Kyrgyz are genetically situated closer to the European than to the East Asian cluster. The present results agree well with the admixture hypothesis that Kyrgyz have not only been derived from Mongoloid, but also Caucasoid ancestors.