BACKGROUND: Cerebral cavernous malformation is a vascular disease of the brain 
causing headaches, seizures, and cerebral hemorrhage. Familial and sporadic 
cases are recognized, and a gene causing familial disease has been mapped to 
chromosome 7. Hispanic Americans have a higher prevalence of cavernous 
malformation than do other ethnic groups, raising the possibility that affected 
persons in this population have inherited the same mutation from a common 
ancestor.
METHODS: We compared the segregation of genetic markers and clinical cases of 
cavernous malformation in Hispanic-American kindreds with familial disease; we 
also compared the alleles for markers linked to cavernous malformation in 
patients with familial and sporadic cases.
RESULTS: All kindreds with familial disease showed linkage of cavernous 
malformation to a short segment of chromosome 7 (odds supporting linkage, 
4X10(10).1). Forty-seven affected members of 14 kindreds shared identical 
alleles for up to 15 markers linked to the cavernous-malformation gene, 
demonstrating that they had inherited the same mutation from a common ancestor. 
Ten patients with sporadic cases also shared these same alleles, indicating that 
they too had inherited the same mutation. Thirty-three asymptomatic carriers of 
the disease gene were identified, demonstrating the variability and age 
dependence of the development of symptoms and explaining the appearance of 
apparently sporadic cases.
CONCLUSIONS: Virtually all cases of familial and sporadic cavernous malformation 
among Hispanic Americans of Mexican descent are due to the inheritance of the 
same mutation from a common ancestor.