is a genetic disorder that causes abnormal development of multiple parts of the body. Characteristics of the syndrome include a distinctive facial appearance, short stature, a broad or webbed neck, congenital heart defects, bleeding problems, skeletal malformations, and developmental delay. Noonan syndrome may be caused by mutations in any one of several genes including the PTPN11, KRAS, RAF1, SOS1, NRAS and BRAF genes. It is sometimes referred to as a specific subtype based on the specific, mutated gene that causes the syndrome in an affected individual. It is typically inherited in an autosomal dominant manner, although in many individuals with Noonan syndrome, the mutation occurs for the first time and neither of the parents has the condition. Source: Genetic and Rare Diseases Information Center (GARD), supported by ORDR-NCATS and NHGRI.