Variations in RASA1 and EPHB4 in Chinese patients with capillary malformation-arteriovenous malformation.

Capillary malformation-arteriovenous malformation (CM-AVM) is a genetic condition predominantly attributed to variations in the RASA1 or EPHB4 genes. We identified three genetic variations: a variation in the RASA1 (c.2603+1G>A) and two novel variations in the EPHB4 (c.53-2A>G and c.2222T>C), expanding the spectrum of variants associated with CM-AVM. Additionally, we found that the presence of EPHB4 variations in these two families, alongside a documented history of Bier spots, highlights the impact of genetic factors on disease phenotype. We also conducted 595 nm pulsed dye laser therapy on the proband 2, and observed that facial telangiectasia was significantly reduced after the laser treatment. We aim to enhance the understanding of the disease through case studies of three families.