Cavernous malformations of the brain are vascular lesions which are present in up to 0.4% of all individuals and which are often accompanied by seizures, migraine, hemorrhage and other neurologic problems. Using linkage analysis and a set of short tandem repeat polymorphisms, a gene responsible for cavernous malformations in a large Hispanic kindred was mapped to the q11-q22 region of chromosome 7. A maximum pairwise lod score of 4.2 was obtained at zero recombination with marker PY5-18 at locus D7S804. Lod scores in excess of 3.0 were obtained with four additional markers closely linked to PY5-18. A broad chromosome 7q haplotype of 33 cM length on the sex average map was shared by all affected individuals indicating that the gene lies between loci D7S502 and D7S479. / 1995 Oxford University Press.