MOLECULAR ANALYSIS OF GB-VIRUS-C ISOLATES IN BELGIAN HEMODIALYSIS-PATIENTS

GB virus C (GBV-C) has been detected in Belgian hemodialysis patients. To study their genomic diversity and phylogenetic relationship, a 592 nucleotide fragment extending from the 5' non-coding region to part o f the El gene of the GBV-C genome was amplified and sequenced from 12 Belgian hemodialysis patients in two different centers. Together with strains from different geographical origins, these sequences were anal yzed phylogenetically using three different methods. A consistent tree topology was obtained with all methods. Three GBV-C genotypes were ob served with two subtypes in type 2 and a questionable subtyping in typ e 1. Except for one isolate falling into type 1 cluster which mainly c onsists of African strains, all the other Belgian strains clustered wi thin the type 2a branch. Two GBV-C isolates in two patients from the s ame hemodialysis center clustered together closely, suggesting a nosoc omial transmission. In view of their long branch length, it seems unli kely that the other Belgian strains evolved recently from a common anc estor. Our results indicate that the major type circulating among Belg ian hemodialysis patients seems to be 2a, which is usual for Europe an d North America, but that the African type 1 also exists to a minor ex tent. Although patient to patient transmission of GBV-C in Belgian hem odialysis centers did occur, it may not account for the majority of in fections. (C) 1998 Wiley-Liss, Inc.