CHARACTERIZATION OF THE HLA CLASS-I GENOTYPES OF A VENEZUELAN AMERINDIAN GROUP BY MOLECULAR METHODS

We have characterized the HLA class I genotypes of the Yucpa, a tribe of Venezuelan Amerindians, using molecular methods. The study was carr ied out on DNA extracted from unrelated individuals using low resoluti on ARMS-SSP typing with sequence-specific primers, high resolution typ ing using reference strand conformation analysis (RSCA), and for some samples sequence-based typing (SBT). The following class I alleles wer e found to be present in this tribe: for the HLA-A locus A0204, A*021 2, A0213, A*2402, A*3101 and A*6801; for the B locus B*1522, B*3512, B3905, B*3909, B*4004 and B*52012, and for C locus Cw*0102, Cw*0302/4 , Cw0401, Cw*0702 and Cw*1503. This is the first time these alleles h ave been described in this group, although all of them have previously been reported as being present in other Amerindian tribes. The study confirmed the high frequency of HLA-B39 which was previously observed in serological analysis of this tribe, and indicated that two differen t B39 alleles were present in this population. The identification of the class I alleles by molecular methods for this ethnic group confirm s the restricted polymorphism of the MHC molecules previously obtained by serology and has allowed a more accurate definition of the differe nt alleles present in this population.