- Mutations in the gene encoding KRIT1, a Krev-1/rap1a binding protein, cause cerebral cavernous malformations (CCM1). Sahoo, T., Johnson, E.W., Thomas, J.W., Kuehl, P.M., Jones, T.L., Dokken, C.G., Touchman, J.W., Gallione, C.J., Lee-Lin, S.Q., Kosofsky, B., Kurth, J.H., Louis, D.N., Mettler, G., Morrison, L., Gil-Nagel, A., Rich, S.S., Zabramski, J.M., Boguski, M.S., Green, E.D., Marchuk, D.A. Hum. Mol. Genet. (1999)