2014 ESC Guidelines on diagnosis and management of hypertrophic cardiomyopathy: the Task Force for the Diagnosis and Management of Hypertrophic Cardiomyopathy of the European Society of Cardiology (ESC).
Duplication of Glu37 in the switch I region of HRAS impairs effector/GAP binding and underlies Costello syndrome by promoting enhanced growth factor-dependent MAPK and AKT activation.
Costello syndrome (CS) is due to mutations in HRAS, with the most common mutation being c.34G>A (p.G12S), found in most patients in all the published series.
Two disease-associated mutations, G12V and G12S, have previously been observed in patients with Costello syndrome (CS), and two other mutations, E63K and Q22K, are novel.