The etiologic role of sex hormones in rheumatoid arthritis (RA) has been discussed. Cytochrome P450c 17 alpha (CYP17) regulates steroidogenesis and the restriction fragment length polymorphisms (RFLPs) of the CYP17 gene are related to serum sex hormone production. In this study, the relationship between CYP17 gene RFLPs and RA was investigated.
Genomic DNA was extracted from the peripheral blood of 91 male and 285 female patients with RA, as well as from 380 male and 579 female controls, and the RFLPs of the CYP17 gene (denoted as the A1 and A2 alleles) were determined. Clinical variables were recorded for the RA patients.
There were no significant differences in CYP17 genotype distribution between the male RA patients and male controls, nor between the female RA patients and female controls. RA patients with the A2 allele tended to develop the disease at a younger age than those without (in men 50.1 vs 54.7 yrs, p = 0.15; in women 43.9 vs 47.4 yrs, p = 0.038). In women, having the A2 allele was a weak protective factor against developing RA at an older age (odds ratio: 0.63, 95% confidence interval: 0.41-0.95, p = 0.026).
The RFLPs of the CYP17 gene may constitute a disease modifying factor through sex hormone production.