DETECTION OF AN EPSTEIN-BARR-VIRUS VARIANT IN T-CELL-LYMPHOMA TISSUES IDENTICAL TO THE DISTINCT STRAIN OBSERVED IN NASOPHARYNGEAL CARCINOMA IN THE TAIWANESE POPULATION

An EBV variant has been identified in NPC tissues in Taiwan. This EBV variant contains a point mutation in exon 1 of the LMP 1 gene. This mutation results in the loss of an Xhol site at nt 169,426, which is present in strain B95-8. In addition, this variant contains a 30-bp deletion in exon 3 of the gene. The recent demonstration of the prevalence of EBV-containing nasal and peripheral T-cell lymphoma in this region drove us to evaluate the presence of this NPC-EBV strain in 7 cases of T-cell lymphoma, as well as in 48 NPC tissues, 2 cases of Hodgkin's disease and 1 B-cell lymphoma. Four samples of normal lymphnode tissue, 40 of normal nasopharynx tissue and 78 throat washings of healthy individuals were included for comparison. We used sequence-specific primers and the polymerase chain reaction (FOR) method to amplify LMP 1 gene fragments containing these variations. Mutations were then confirmed by restriction-enzyme digestion and the DNA sequencing analysis. Our results showed that 57 of 58 tumor-tissues samples were EBV-positive. Among them, 56, including 6 T-cell-lymphoma samples, belonged to the NPC strain. This strain of EBV was also present in 92% of EBV-positive normal nasopharynx tissues and in 84% of EBV-positive throat washings of the healthy individuals tested. These results suggest that the NPC-EBV strain is prominently present in Taiwan. (C) 1995 Wiley-Liss, Inc.