A MOLECULAR STUDY OF EBV DNA AND P53 MUTATIONS IN NASOPHARYNGEAL CARCINOMA OF SAUDI-ARAB PATIENTS

Tumor biopsies obtained from 25 Saudi Arab patients with nasopharyngea l carcinoma (NPC) were examined for the presence of Epstein-Barr virus (EBV) DNA detected by the polymerase chain reaction (PCR) and for the incidence of p53 mutations screened by a combination of PCR, single s trand conformation polymorphism (SSCP) and PCR-restriction fragment le ngth polymorphism (PCR-RFLP). DNA sequencing was carried out to confir m the occurrence of p53 mutation. While 92% of the tumor specimens wer e found to carry EBV DNA, only 1/25 showed the incidence of a homozygo us mutation at codon 248 of the p53 gene. The data showed that despite a high association of EBV infection with Saudi NPC, the frequency of p53 mutations was very low. Our results are consistent with the worldw ide observation of infrequent p53 mutations in NPC.