Homozygous deletion genotype of angiotensin converting enzyme confers protection against migraine in man.

Studies have shown that migraine may have a major genetic component. Meanwhile, angiotensin converting enzyme (ACE) gene has been implicated as a genetic factor associated with migraine. We designed a case-control study to investigate the association between ACE and migraine in 240 migraine patients and 200 healthy controls, matched by age and sex. There was no significant difference in allelic frequency (I and D) and genotype polymorphism (DD, DI and II) of the ACE gene in migraine patients and controls. Analysis of the difference in ACE polymorphism stratified by gender revealed that male migraine patients with the homozygote DD genotype (ACE-DD) were significantly fewer than that of male controls (OR = 0.331, p = 0.045). There was no existence of a difference among the frequency and duration of headache in each subgroup of migraine patients stratified by ACE genotype. Our findings indicate that ACE-DD may have a slight protective effect against migraine in male patients.