Association study of a functional variant in intron 8 of the dopamine transporter gene and migraine susceptibility.

Migraine is a common, genetically influenced neurovascular disorder. The dopamine transporter gene is a candidate for migraine association studies. This study tested a functionally linked variable number tandem repeat (VNTR) in intron 8 of the dopamine transporter gene (DAT(Int8)) in 550 migraine cases (401 with aura, 149 without aura) and 550 non-migraine controls. Chi-squared analysis of the DAT(Int8) revealed that the allele and genotype frequency distributions for migraine cases (including subtype analysis) and controls were not different (P > 0.1). These findings offer no evidence for an association of the DAT(Int8) with migraine with and without aura and therefore do not implicate the dopamine transporter gene as a modifier of migraine risk.