KRIT1

Cerebral cavernous malformation

More than 100 KRIT1 gene mutations have been identified in families with cerebral cavernous malformations, which are collections of blood vessels in the brain that are weak and prone to leakage. Virtually all of these mutations place a premature stop signal in the instructions for making the KRIT1 protein, preventing adequate KRIT1 protein production. A shortage of this protein likely impairs the function of the complex. As a result, RhoA-GTPase signaling is turned on abnormally, weakening cellular junctions and increasing the permeability of blood vessel walls. The increased leakage into the brain can cause health problems such as headaches, seizures, and bleeding in the brain (cerebral hemorrhage) in some people with cerebral cavernous malformations.

Mutations in the KRIT1 gene account for up to 50 percent of all familial cerebral cavernous malformation cases. One particular mutation is responsible for up to 70 percent of cases in people of Hispanic heritage. This mutation changes a single DNA building block (nucleotide) at position 1363 in the KRIT1 gene, written as 1363C>T.