Noonan syndrome (NS)

What is Noonan syndrome (NS)?

Noonan syndrome (NS) is a genetic disorder that can be inherited from one or both parents. Noonan syndrome prevents normal development and causes many problems throughout a child’s body. The most common problems include heart conditions and skeletal malformations.

Noonan syndrome has other names including:

• Noonan-Ehmke syndrome

• Pseudo-Ullrich-Turner syndrome

• Turner phenotype with normal karyotype

• Turner syndrome in female with X chromosome

• Ullrich-Noonan syndrome

Risk factors

Your child is at risk for Noonan syndrome (NS) if one or both parents carry the defective gene.

What are the signs and symptoms of Noonan syndrome (NS)?

The most common symptoms of Noonan syndrome (NS) include:

• Bleeding disorders

• Congenital (present at birth) heart defect

• Deep groove between the nose and mouth

• Excess neck skin

• High-arched palate

• Low hairline at back of the neck

• Low set ears, rotated backward

• Scoliosis (abnormal spinal curve)

• Short neck

• Short stature

• Skeletal malformations

• Small lower jaw

• Sunken or protruding chest wall

• Wide spaced eyes

What are the causes of Noonan syndrome (NS)?

Noonan syndrome is a genetic disorder, meaning that a gene inherited from one or both parents is defective. During fetal development, Noonan syndrome is caused by changes in one of several dominant genes.