Cerebral cavernous malformation (CCM), which leads to thin-walled vascular cavities and haemorrhages in the brain, is caused by loss-of-function mutations in the CCM1–3 genes [126], and the loss of CCM function is accompanied by reduced Notch signalling and a disruption of Notch signalling between ECs and pericytes [127,128]. This evidence concerns the gene KRIT1 and cerebral cavernous malformation.