Molecular genetic investigations in the CCM1 gene in sporadic cerebral cavernomas

Abstract
Objective: Cerebral cavernous malformations (CCM) occur in familial and sporadic forms that cannot be distinguished by phenotype. Mutations in Krit1, a gene located at the CCM1 locus on chromosome 7q21, account for the majority of familial CCM cases. The authors investigated the role that mutations at the CCM1 locus play in sporadic cavernomas and the prevalence of occult familial forms among symptomatic cavernomas. Methods: The authors screened the DNA of cavernomas and adjacent normal brain tissue of 72 consecutive patients treated at the Neurosurgical Department/Ludwig-Maximilian University for mutations in Krit1. Eight of the patients had been suspected to have a mutation at CCM1, as they showed multiple cavernomas or clinically familial forms. Results: None of the patients showed a mutation at the CCM1 site, either in cavernomas or in normal brain tissue. Conclusion: Mutations in Krit1 are seldom a cause of sporadic cavernomas.