Epstein-Barr virus (EBV) has been implicated in various diseases, among others, nasopharyngeal carcinoma (NPC). In this study we investigated the frequency and subtype distribution of EBV in 39 NPCs. The presence of EBV was detected by using a nested PCR to amplify the Bam Hl W-fragment of the genome. Two regions were targeted for subtype analysis, namely the EBNA-2A and EBER regions. PCR was used to amplify these regions, and the EBER region was sequenced to detect subtype specificity. The results showed that EBV could be detected in 82% (31/38) of the tumours. In 15 of these, EBNA subtypes could be identified of which 14 were subtype A and one tumour had both subtypes A and B present. The EBER region was amplified in 21 samples. The majority of cases (18/21) demonstrated a mutation profile which consisted of 5 type B and one type A mutations. The consensus type is therefore type B.
In conclusion: a strong association was found between EBV and NPCs in our group of patients and their "consensus" genotype was A/B based on the two genome areas investigated.