Objective: To explore the association of T1270533G polymorphism in the glutathione S-transferase M1 (GSTM1) gene with the susceptibility to nasopharyngeal carcinoma (NPC) and clinical phenotype of NPC in Chinese population. METHDOS: The genomic DNAs were obtained from 27 Chinese subjects, and the single nucleotide polymorphism (SNP) in all the exons and relevant intron-exon boundaries of GSTM1 were determined by PCR and direct sequencing. A case-control study was performed to analyze the SNP site T1270533G (the rare allele frequency is 22.2% in Chinese population) in the coding region by means of tetra-primer amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and sequencing.
Result: Sequence analysis identified 29 SNPs in GSTM1 gene, among which 13 SNPs presented high linkage disequilibrium with each other. No obvious relations were found between the variation in the coding region T1270533G and the clinical phenotype of NPC (RR=0.170, 95% CI =0.95-0.306 for TT homozygotes).
Conclusion: The missense mutation in the coding region T1270533G of GSTM1 gene that causes an amino acid change does not affect the detoxification function of GSTM1, and the T1270533G polymorphism does not have apparent relations to NPC susceptibility in Chinese subjects in Guangdong Province.