Abstract
Use of the Kaposi's sarcoma-associated herpesvirus ( KSHV) bacterial artificial chromosome 36 (KSHV-BAC36) genome permits reverse genetics approaches to study KSHV biology. While sequencing the complete KSHV-BAC36 genome, we noted a duplication of a 9-kb fragment of the long unique region in the terminal repeat region. This duplication covers a part of open reading frame (ORF) 19, the complete ORFs 18, 17, 16, K7, K6, and K5, and the putative ORF in the left origin of lytic replication, and it contains the BAC cassette. This observation needs to be kept in mind if viral genes located within the duplicated region are to be mutated in KSHV-BAC36.