Relative map locations within the ORF25 and ORF26 of HHV-8 genome of the three nested-PCR (N-PCR1, N-PCR2, and N-PCR3) used as a diagnosis purpose for HHV-8 DNA sequence detection, of the N-PCR4, used to obtain a 334-bp amplicon from the ORF26 DNA target, and of the N-PCR5, used to obtain a 494-bp amplicon from the ORF75 DNA target, sufficiently large to allow genetic variability analysis after direct DNA sequencing. The 17.4-kb divergent locus-B of the HHV-8 genome, supporting the vIL-6 and the bcl-2–like genes,61 and the ORFs within the 20.7-kb KS5 fragment of HHV-8,1 are shown in comparison with other equivalent loci and known genes in the herpesvirus Saimiri (HSV). The upper portion of the figure illustrates the arrangement of the ORFs in a contiguous 55-kb block at the left-hand end of the HSV genome: solid bars refer to ORFs that are common in all known γ-Herpetovirinae, shaded bars indicate ORFs that are found in several γ2-Herpetovirinae, and open bars denote ORFs that are unique to HSV. The ORF25 of HHV-8 is thought to be translated into a major capsid protein and the ORF26 into a virion protein.1