Vitamin D receptor gene TaqI single nucleotide polymorphism is not associated with lead levels in maternal and umbilical cord blood

Abstract

Purpose: We aimed to investigate the association of vitamin D receptor (VDR) gene TaqI single nucleotide polymorphism (SNPs) with serum lead (Pb) levels in maternal and umbilical cord blood. Materials and methods: Eighty-one patients who lived in Konya, Turkey for the last 3 years and had delivery at Baskent University Konya Hospital in 2016 were included in this study. Venous blood samples were drawn from each volunteer immediately before giving birth to determine the maternal Pb levels and VDR SNPs. Additionally, umbilical cord blood samples were collected from the umbilical vein into tube with EDTA as an anticoagulant immediately after birth to determine Pb levels of the fetus. Results: The median level of Pb in the maternal blood was 29.00 (Interquartile Range (IQR) = 16.35) mu g/L and the median Pb level in the cord blood was 22.50 (IQR = 9.75) mu g/L. Blood Pb level of women living in the urban area was significantly higher than in those living in the rural area (Z = 2.118; p = .034). There was a very strong positive correlation between the Pb levels in the maternal blood and in the umbilical cord blood (rho = 0.825, p < .001, respectively). Regarding VDR SNPs, "TT", "TC", and "CC" VDR TaqI genotypes were observed in 28 (34.6%), 45 (55.5%), and eight samples (9.9%), respectively. Pb levels in maternal and cord blood were higher in women with the "CC" VDR TaqI genotype; however, there was no statistically significant difference (p > .05). Conclusions: Although women with the "CC" VDR TaqI genotype had higher maternal and cord blood Pb levels, this was statistically insignificant and therefore, VDR TaqI SNPs did not significantly affect maternal and umbilical cord blood Pb levels.