Result: The mutation at residue R163M was detected in all samples in the self-association domain.

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Discussion: Of the three common mutations, amino acid mutation R163M and silent mutation c48998a were previously identified in 13 Korean isolates, 18 of 33 oral squamous cell carcinoma cases in Okinawa, Japan and 6 human immunodeficiency virus-infected patients and the NPC samples in Hong Kong or Canton.

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Discussion: The mutation R163M, which was located in the self-association (aa 148-214) domain of EBNA-2, was detected in all samples.

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