Association between ε2/3/4, promoter polymorphism (-491A/T, -427T/C, and -219T/G) at the apolipoprotein E gene, and mental retardation in children from an iodine deficiency area, China.

Association between ε2/3/4, promoter polymorphism (-491A/T, -427T/C, and -219T/G) at the apolipoprotein E gene, and mental retardation in children from an iodine deficiency area, China.