Absence of alpha-1 antitrypsin deficiency alleles (S and Z) in Japanese and Korean patients with aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE A possible association has been proposed for the formation of intracranial aneurysm (IA) and deficiency alleles (S and Z) of the alpha1-antitrypsin (AAT) gene. We extensively screened this gene in Japanese and Korean patients with aneurysmal subarachnoid hemorrhage. METHODS Seven allelic variants, including S and Z alleles, were genotyped by direct sequencing of genomic DNA obtained from 195 and 189 ruptured IA patients and 195 and 94 controls in Japanese and Koreans, respectively. The haplotype in phase-unknown samples was constructed with the expectation-maximization method. Differences in allelic frequencies between patients and controls were evaluated by Fisher exact test. RESULTS No significant differences in allelic frequencies were observed at all 7 variants between ruptured IA patients and controls. We could not detect the S and Z alleles of the AAT gene in Japanese and Korean populations. CONCLUSIONS AAT deficiency may not be a common genetic risk factor for aneurysmal subarachnoid hemorrhage in Japanese and Koreans.