A novel CCM1 gene mutation causes cerebral cavernous malformation in a Chinese family.

Familial cerebral cavernous malformations (CCMs) are characterized by an autosomal dominant transmission with incomplete penetrance. We have previously reported a 1292delAT mutation in the CCM1 gene in a Chinese family with CCM. Here we report a novel deletion of CCM1 that correlates strongly with CCM formation in another family. Ten affected family members were observed among the 25 participants, and multiple CCM lesions were detected in seven individuals. Nucleotide sequencing analysis in the index patient and other affected members showed a CAAA deletion in exon 12 at nucleotide (NT) 1197. We predict this deletion produces a premature stop code (TGA) at NT 1228, resulting in a truncated protein of 409 amino acids.