Prevalence of Fabry disease and GLA c. 196G> C variant in Japanese stroke patients

Fabry disease is an important underlying disease in young cryptogenic stroke patients. However, little is known regarding the frequency of Fabry disease in the general stroke population, especially in elderly patients. A total of 588 stroke patients (61.7% men; average age 74.1 +/- 12.5 years) were enrolled in this prospective study. Blood samples were obtained to produce blood spots to determine alpha-galactosidase A (alpha-GalA) activity and for GLA gene analysis. One 65-year-old female patient had a known GLA gene mutation, c. 2T > C (p.M1T), causing Fabry disease. Five male patients and two female patients had GLA c. 196G > C (p.E66Q) variant, which is not associated with the full clinical manifestations of Fabry disease. The allele frequency of GLA c. 196G > C was significantly higher in male patients with small-vessel occlusion (odds ratio 3.95, P=0.048) and non-cardioembolism (odds ratio 4.08, P=0.012) than that in the general Japanese population. Fabry disease is rare in the general Japanese stroke population. However, screening identified one elderly female patient with Fabry disease. GLA c. 196G > C variant is a genetic risk factor for cerebral small-vessel occlusion and non-cardioembolism in Japanese males but not in females.