Association of TNF, MBL, and VDR polymorphisms with leprosy phenotypes

Although genetic variants in tumor necrosis factor (TNF), mannose binding lectin (MBL), and the vitamin D receptor (VDR) have been associated with leprosy clinical outcomes, these findings have not been extensively validated. We used a case-control study design with 933 patients in Nepal, which included 240 patients with type I reversal reaction (RR), and 124 patients with erythema nodosum leprosum (ENL) reactions. We compared genotype frequencies in 933 cases and 101 controls of seven polymorphisms, including a promoter region variant in TNF (G -308A), three polymorphisms in MBL (C154T, G161A and G170A), and three variants in VDR (FokI, BsmI, and TaqI). We observed an association between TNF -308A and protection from leprosy with an odds ratio of 0.52 (95% confidence interval = 0.29-0.95, p = 0.016). MBL polymorphism G161A was associated with protection from lepromatous leprosy (odds ratio = 0.33, 95% confidence interval = 0.12-0.85, p = 0.010). VDR polymorphisms were not associated with leprosy phenotypes. These results confirm previous findings of an association of TNF -308A with protection from leprosy and MBL polymorphisms with protection from lepromatous leprosy. The statistical significance was modest and will require further study for conclusive validation.