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This is a clinical test intended for Help: Diagnosis, Mutation Confirmation

Clinical summary


Imported from GeneReviews

Noonan syndrome (NS) is characterized by characteristic facies, short stature, congenital heart defect, and developmental delay of variable degree. Other findings can include broad or webbed neck, unusual chest shape with superior pectus carinatum and inferior pectus excavatum, cryptorchidism, varied coagulation defects, lymphatic dysplasias, and ocular abnormalities. Although birth length is usually normal, final adult height approaches the lower limit of normal. Congenital heart disease occurs in 50%-80% of individuals. Pulmonary valve stenosis, often with dysplasia, is the most common heart defect and is found in 20%-50% of individuals. Hypertrophic cardiomyopathy, found in 20%-30% of individuals, may be present at birth or develop in infancy or childhood. Other structural defects include atrial and ventricular septal defects, branch pulmonary artery stenosis, and tetralogy of Fallot. Up to one fourth of affected individuals have mild intellectual disability, and language impairments in general are more common in NS than in the general population.

Conditions tested

Target population


Mainly cases with some clinical characteristic feature associated with any of the RASopathy-related syndrome where it is needed a genetic confirmation (complete study) or in cases where the analysis is needed to detect the presence of a previously identified mutation in a family (direct study).


Not provided

Clinical validity


Not provided

Clinical utility


Establish or confirm diagnosis

Guidance for management

Reproductive decision-making

Predictive risk information for patient and/or family members

Lifestyle planning

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