Heterozygous HTRA1 mutations with mimicking symptoms of CARASIL in two families.

The term cerebral small vessel disease (SVD) refers to a group of pathological processes with various etiologies that affect the small arteries, arterioles, venules, and capillaries of the brain. SVD occurs in approximately 5% of patients. Cerebral autosomal recessive arteriopathy with subcortical infarcts and leukoencephalopathy (CARASIL),a recessive form of heritable SVD, is caused by a mutation in the high temperature requirement A serine peptidase (HTRA1) gene. Recently, heterozygous mutations in HTRA1 were identified in patients with symptomatic SVD. We identified two families harboring HTRA1 (p.S284 N and p.V216 M) heterozygous mutations with symptoms that mimicked common symptoms of CARASIL.