MAP3K3 and cerebrocostomandibular syndrome: Similarly, sporadic CCMs may involve postzygotic variants in PIK3CA and additional variants in the CCM genes or in MAP3K3. Interestingly, sporadic CCMs often arise near developmental venous anomalies (DVA), a type of brain venous malformation caused by somatic PIK3CA variants, which may serve as a primer for CCMs (Petersen et al, 2010; Snellings et al, 2022).