Molecular epidemiology of human herpesvirus 8 in Africa: Both B and A5 K1 genotypes, as well as the M and P genotypes of K14.1/K15 loci, are frequentand widespread

We have studied 52 new HHV8 strains by sequencing the complete hypervariabl e Ki gene and genotyping the K14.1/K15 loci located at both sides, respecti vely, of the viral genome. The samples originated from 49 patients with Kap osi's sarcoma (KS; 32 patients), multicentric Castleman's disease (MCD; 12 patients), or primary effusion lymphoma (PEL; 5 patients). Among these pati ents, 32 were of African origin (West and Central African countries and Cre oles from French Guiana) and the 17 others were mostly French homosexuals. Comprehensive phylogenetic studies allowed the identification of distinct g roups within the three already known main subtypes. Interestingly, two new sequences that did not cluster within a known subtype or group could be con sidered as prototypes of early/ancient variants of the C subtype and A/C se t, respectively, Among the 32 African strains, the majority were either of the B subtype (13 cases) or of the A5 group (11 cases), indicating that thi s latter genotype is frequent and widespread in Africa. In contrast, a subt ype C strain infected most of the 17 other patients. PCR-based genotyping o f the K14.1/K15 loci revealed an overall predominance of P subtype, except in the A5 and a K1 groups, in which the P and M alleles were equally repres ented. The implications of these data on the evolution and spread of HHV8 a mong human African populations are discussed. (C) 2000 Academic Press.