IDENTIFICATION OF A UNIQUE GROUP OF HUMAN PAPILLOMAVIRUS TYPE-16 SEQUENCE VARIANTS AMONG CLINICAL ISOLATES FROM BARBADOS

The naturally occurring sequence variation of human papillomavirus typ e 16 (HPV-16) was analysed by direct sequence analysis of the PCR prod ucts of the long control region (LCR), the E5 and E7 open reading fram es (ORFs), a segment of the L2 ORF overlapping the early viral poly(A) signal and a small segment of the L1 ORF or clinical isolates from Ba rbados and The Netherlands. Despite the widely different geographical and ethnic origin of the two groups of specimens, sequence analysis re vealed relatively few mutational differences. Analysis of the LCR and the E5 ORF appeared to be the minimum requirement for the correct posi tioning of these variants in the HPV-16 phylogenetic tree. Most of the Barbadian variants appeared to be located at a unique position in the HPV-16 phylogenetic tree, at the internal branch close to the point w here the European and Asian branches diverge. In contrast, most of the Dutch samples were located on the European branch.