Background: The dopam ine m etabolism is believed to play an important part in the pathophysiology of migraines. It was reported that the distribution of alleles for the dopamine D4 receptor gene (DRD4) in migraine w ithout aura patients is significantly different from those in control group. A polymorphism of the D RD4 m ight be related to genetic susceptibility of m igraine. The aim of this study w as to investigate the association of DRD4 exon III polymorphism between patient group w ith m igraine and control group.
Methods: This study compared 150 patients with m igraine (38 m ales, 112 females and m ean age 42.4±10.23) 100 healthy control subjects (25 males, 75 females and mean age 42.6±10.35) in order to determine the association between a polymorphism of the DRD4 exon III and m igraine. Using PCR techniques, the DRD4 polymorphism was denoted by 48-base-pair tandem repeat in exon III of the gene.
Results: There w as no significant difference between the healthy controls, m igraine without aura patients and m igraine with aura patients in age and sex distribution. Significant differences w ere noted in the genotype betw een m igraine without aura group and m igraine w ith aura group. Also significant differences w ere observed in allele frequencies compared m igraine w ithout patients w ith control group and m igraine w ith aura patients.
Conclusions: The DRD4 polymorphism appears to be involved in the genetic predisposition to m igraine w ithout aura. Migraine w ithout aura m ay have different pathophysiology from m igraine w ith aura in genetic field.