CADASIL and CADASIL-like families in Japan

Cerebral autosomal dominant arteriopathy. with subcortical infarcts and leu koencephalopathy (CADASIL) is an adult-onset disorder presenting as vascula r dementia associated with mutations of Notch3 gene. To clarify the occurre nce of CADASIL in Orientals, we performed clinicogenetic studies for 5 unre lated Japanese families presenting as CADASIL. On mutational analysis of No tch3 gene, we identified R133C mutation in two unrelated families including 5 affected individuals. Their clinicopathological findings shared similar patterns as European CADASIL families. Other 3 unrelated families including 18 affected individuals presenting with CADASIL-like clinical features dis closed no mutations of Notch3 gene. Thus, the results indicate that CADASIL is a geographically widespread disorder, and there are unknown hereditary arteriopathies resulting in vascular dementia without Notch3 mutations in J apan.