Association of vitamin D receptor (VDR) gene polymorphism with blood lead levels in occupationally lead-exposed male battery workers in Delhi – National capital region, India

Abstract

Lead is a well-known environmental pollutant due to its widespread industrial uses and persistent nature. Studies have underlined the toxicities caused due to occupational exposure to lead and have also reported the association of blood lead levels (BLL) with Vitamin D Receptor (VDR) gene polymorphism; however, such data is scarce from India. This maiden attempt aims to investigate the association of different VDR polymorphic variants on BLL in the north-Indian lead-exposed population. We recruited 100 occupationally lead-exposed battery workers (LEBW) and 100 non-lead exposed controls (NLEC). BLL, serum Vitamin D, calcium and phosphorous levels were measured. Further, VDR polymorphisms namely, FokI, TaqI, ApaI, and BsmI polymorphic variants were studied. Results demonstrated that BLL was significantly increased in LEBW as compared to NLEC. Chi-square test results show that frequencies of Ff FokI VDR genotype and bb BsmI VDR genotype were significantly more in LEBW as compared to NLEC (P =0.02 and 0.03, respectively). Furthermore, FF, aa and bb genotype showed the highest BLL in LEBW indicating higher lead levels in some VDR polymorphisms.