Table 7.

Somatic disorders involving arteriovenous malformations.

Associated malformation or syndrome	Clinical phenotype	Candidate gene	Protein function or suspected role (if known)	Clinical work-up	References
Sporadic AVM	• Abnormal connections between arteries and veins without a normal capillary bed	MAP2K1/MEK1 KRAS	• Stimulates enzymatic activity of MAP kinases	• Imaging with MRI and/or angiography	(3, 10, 11, 54–56)
	• Results in arterialization of venous system, pain, tissue destruction, and bleeding complications	NRAS BRAF	• Intracellular RAS/MAPK signaling	• Thorough exam/history to exclude HHT or CM-AVM