ETHNIC SEGREGATION OF HTLV-I AND HTLV-II CARRIERS AMONG SOUTH-AMERICAN NATIVE INDIANS

To investigate the genetic background of human T-cell leukemia virus t ype I (HTLV-I) and II (HTLV-II) carriers among South American native I ndians, we analyzed HLA DRB1-DQB1* haplotypes of the virus carriers f rom Andes highlands and Orinoco lowlands by the PCR-RFLP genotyping me thod. It was revealed that the HTLV-I-carrying Andes natives had one o f the 5 HLA haplotypes: DRB1-DQB1* 0403-0302, 0802-0402, 0901-0303, 1 406-0302 and 0407-0302, and that the Orinoco HTLV-II carriers had one of the 3 HLA haplotypes: DRB1DQB1* 1402-0301, 1602-0301 and 0404-0302 . The HLA haplotypes of Andes HTLV-I carriers and Orinoco HTLV-II carr iers were mutually exclusive. The haplotypes associated with HTLV-I ca rriers were commonly found among the Andes Indians and Japanese, which is the known HTLV-I endemic population, while the haplotypes associat ed with HTLV-II carriers were specifically found among the Orinoco Ind ians and North American Indians, among whom HTLV-II is endemic. These results suggested that HLA haplotypes might be ethnically segregated a mong South American natives and might be involved in the susceptibilit y to HTLV-I and HTLV-II infections. (C) 1995 Wiley-Liss, Inc.