Objective: The relationship between polymorphisms of ALAD and VDR genes and individual susceptibility of lead poisoning was investigated in children highly-exposed to lead.
Method: Four hundred and sixty-nine children were recruited into this study and the blood lead, ZPP, hemoglobin as well as three physical developmental indexes (head circumference, height and weight) were measured. VDR and ALAD gene polymorphisms were analyzed by the methods of PCR-RFLP.
Results: The subjects with ALAD2 allele had higher ZPP level (10.12 micro mol/L vs 12.87 micro mol/L) (P = 0.017). The subjects with B allele has larger head circumference than only with b allele (51.19 cm vs 50.75 cm) (P = 0.028).
Conclusions: It was suggested that the ALAD gene polymorphism modified the relationship between blood lead and ZPP and the VDR gene variants influenced the skull development in children living under lead-polluted environment. The polymorphism of ALAD and VDR genes might serve as the molecular inherited factors modifying the susceptibility of lead poisoning.