Sindrome di Noonan

Noonan Syndrome is a clinically and genetically heterogeneous condition, with autosomal dominant inheritance, characterized by dinstintive facial features, congenital heart defects, postnatal growth retardation (weight and height), variable psycomotor delay, and other comorbidities (involvement of visual, lymphatic, coagulative, genital, skeletal, ectodermic and rarely hematopoietic system). Its estimated prevalence is 1:1,000-1:2,500 live births. Noonan syndrome is caused by mutations in genes coding for proteins with role in RAS-MAPK signal transduction pathway. So far, the identified disease genes (PTPN11, SOS1, KRAS, NRAS, RAF1 and BRAF) allow to confirm the diagnosis molecularly in approximately 75% of affected individuals.