Role of ALAD and VDR genotypes on the association of low blood lead level with serum uric acid and blood pressure in automobile paint workers of Karachi, Pakistan.

Lead is an environmental pollutant having nephrotoxic effects even at low level. Its continuous exposure is associated with increased serum uric acid level that resulting in renal insufficiency. This research was conducted to see the effects of delta-aminolevulinic acid dehydratase (ALAD) and vitamin D receptor (VDR) genotypes on biochemical parameters and blood pressure (BP) of automobile workers having low blood lead level (BLL) with continuous lead exposure. Automobile paints workers with ALAD 1-2 genotype showed the positive association of BLL with diastolic BP (p<0.05) whereas, a genotypic combination of ALAD 1-2/VDR BB showed the negative association of serum uric acid with BLL (p<0.05). Similarly negative effects of VDR BB genotype (p<0.01) and ALAD 1-2 genotype (p<0.05) were observed in the association of serum uric acid with BLL at the mean age ≥30 years. This suggests that automobile paint workers having ALAD 1-2 genotypes are at the risk of increased diastolic BP. The research also foretells that combination of ALAD 1-2/VDR BB may play a significant role against lead induced nephrotoxicity at low BLL with continuous lead exposure.