sentences:  The classical triad of symptoms that defines 3C syndrome includes certain heart defects, hypoplasia (underdevelopment) of the cerebellum, and cranial dysmorphisms, which can take various forms.The heart defects and cranial dysmorphisms are heterogeneous in individuals who are all classed as having Ritscher-Schinzel syndrome.Heart defects commonly seen with Ritscher-Schinzel syndrome are associated with the endocardial cushion and are the most important factor in determining a diagnosis.