Objects: This study aims to clarify the genetic background of moyamoya disease by comparing clinical features between familial and sporadic cases to reveal the responsible genes for familial moyamoya disease.
Methods: This study included 155 Japanese patients with moyamoya disease, which included 24 familial cases (10 family pedigrees) and 131 sporadic cases. Clinical features were compared between the familial and sporadic cases.
Results and conclusion: A female preponderance was significantly more prominent in the familial than in the sporadic group (P=0.0421). Mean age at onset was significantly lower in familial than in sporadic cases (P=0.004). In eight parent-offspring pairs, mean age at onset was significantly lower in the second than in the first generation (P<0.0001). These results suggest that familial moyamoya disease is associated with genetic anticipation and female predominance and that a genetic analysis study focused on expanded triplet repeats may clarify the pathogenesis of the disease.