Association Analysis of Melanocortin 3 Receptor Polymorphisms with the Risk of Pulmonary Tuberculosis

Abstract

Melanocortin 3 Receptor (MC3R) is one of the families of seven-transmembrane G-protein-coupled receptors, and a recent study showed that MCR3 promoter polymorphism was significantly associated with the susceptibility of tuberculosis (TB) in South African population. We analyzed six MC3R polymorphisms to examine the genetic effects on the risk of pulmonary TB in Korean subjects by using TaqMan assays and case-control analyses. Using statistical analyses, one common promoter polymorphism (MC3R rs11575886 T > C) was found to be associated with an increased risk of pulmonary TB. The frequency of the C-bearing genotype of rs11575886 was higher in pulmonary TB patients than in normal controls (p = 0.03, OR = 1.46) although the significance was not retained after correction. In silico analysis for the difference of transcription binding factor (TF), motif between C and T allele demonstrated that the TF motif and its threshold scores of C allele were lower than those of T allele. The C allele of rs11575886 could be a risk allele for the pulmonary TB by affecting the binding of TF. Our findings suggest that polymorphisms in MC3R might be one of genetic factors for the risk of pulmonary TB development in Korean subjects.