A case-control and a family-based association study revealing an association between CYP2E1 polymorphisms and nasopharyngeal carcinoma risk in Cantonese

Nasopharyngeal carcinoma (NPC) is rare in most parts of the world but is more prevalent in Southern China, especially in Guangdong. The cytochrome P450 2E1 (CYP2E1) has been recognized as one of the critically important enzymes involved in oxidizing carcinogens and is probably to be associated with NPC carcinogenesis. To systematically investigate the association between genetic variants in CYP2E1 and NPC risk in Cantonese, two independent studies, a family-based association study and a case-control study, were conducted using the haplotype-tagging single-nucleotide polymorphism approach. A total of 2499 individuals from 546 nuclear families were initially genotyped for the family-based association study. Single-nucleotide polymorphisms (SNPs) rs9418990, rs915908, rs8192780, rs1536826, rs3827688 and one haplotype h2 (CGTGTTAA) were revealed to be significantly associated with the NPC phenotype (P = 0.045-0.003 and P = 0.003, respectively). To follow up the initial study, a case-control study including 755 cases and 755 controls was conducted. Similar results were observed in the case-control study in individuals