DETECTION OF HUMAN HERPES-VIRUS-8 DNA AND SEQUENCE POLYMORPHISM IN CLASSICAL, EPIDEMIC, AND IATROGENIC KAPOSIS-SARCOMA IN SOUTH-AFRICA

The aetiology and detection of human herpes virus type 8 (HHV-8) DNA s equences in Kaposi's sarcoma (KS) is a matter of intense investigation . We report on the detection of HHV-8 DNA and sequence polymorphism in different clinicopathological subtypes of cutaneous KS samples from S outh Africa. The diagnosis was confirmed by histological examination i n all cases. Six patients had classic KS (CKS), 3 epidemic KS (EKS), a nd 3 iatrogenic KS (IKS). A nested polymerase chain reaction (PCR) ass ay was used to detect HHV-8 DNA in cell lysates, prepared from formali n fixed, paraffin embedded sections. We investigated polymorphism in t he HHV-8 DNA using single-stranded conformational polymorphism (SSCP) analysis on the PCR products, followed by direct sequencing. HHV-8 DNA was detected in all the patients with KS, irrespective of the clinico pathological subtype. Direct sequencing was performed on 5 selected ca ses and showed single base pair substitutions in all. The spectrum of mutations was similar to those described previously. No correlation wa s found between the different types of KS and sequence variation. The results support the hypothesis that HHV-8 is strongly associated with different clinicopathological subtypes of KS and confirm the occurrenc e of HHV-8 in patients with CKS, EKS, and IKS in South Africa. (C) 199 7 Wiley-Liss, Inc.