Investigation of the Association between the CYP7A1 A-203C Polymorphism and Barrett’s Esophagus in British Population

Abstract

Cholesterol 7α -hydroxylase (CYP7A1, EC 1.14.13.17) encoded by CYP7A1 gene is the rate-limiting enzyme in synthesis of bile acids from cholesterol in the liver. Polymorphisms in CYP7A1gene can affect CYP7A1 activity, and thus affect cholesterol metabolism and bile acid production. Bile acids have an important role in development of Barrett’s esophagus (BE) which is a condition in which changing of the cells lining the esophagus occurs. They are known extremely toxic substances at high doses. Thus, bile acids and thereby BE, might contribute to cancer. The aim of this pilot study was to investigate the association between the CYP7A1 A-203C polymorphism and BE. In the study, 55 samples from Barrett’s esophagus and 104 samples from control group were analyzed by using a polymerase chain reactionrestriction fragment length polymorphism (PCR-RFLP) technique. No statistical differences between cases and controls were found in the distribution of genotype or allele frequencies. However, the AC genotype was less frequent in the case group (38%) versus controls (51%). The results also showed that crude odds ratio of individuals with the CYP7A1 heterozygote (AC) genotype and Barrett’s esophagus for the CC genotypes versus AA genotypes was 0.528 (95% CI 0.261-1.070; p= 0.077) and 0.622 (95% CI 0.229-1.704; p= 0.363), respectively. The variant C allele may have protective effect with regard to risk of BE. This study is the first to demonstrate the relationship between CYP7A1gene and BE. However, these results need further investigation and confirmation

Keywords

• CYP7A1, Barrett’s esophagus, bile acids, polymorphism