Learn About Noonan Syndrome
Noonan syndrome is a disease present from birth (congenital) that causes many parts of the body to develop abnormally. In some cases it is passed down through families (inherited).
Noonan syndrome is linked to defects in several genes. In general, certain proteins involved in growth and development become overactive as a result of these gene changes.
Noonan syndrome is an autosomal dominant condition. This means only one parent has to pass down the nonworking gene for the child to have the syndrome. However, some cases may not be inherited.
Symptoms include:
- Delayed puberty
- Down-slanting or wide-set eyes
- Hearing loss (varies)
- Low-set or abnormally shaped ears
- Mild intellectual disability (only in about 25% of cases)
- Sagging eyelids (ptosis)
- Short stature
- Small penis
- Undescended testicles
- Unusual chest shape (most often a sunken chest called pectus excavatum)
- Webbed and short-appearing neck
There is no specific treatment. Your provider will suggest treatment to relieve or manage symptoms. Growth hormone has been used successfully to treat short height in some people with Noonan syndrome.
University Of Magdeburg
Martin Zenker is in Magdeburg, Germany. Zenker is rated as an Elite expert by MediFind in the treatment of Noonan Syndrome. He is also highly rated in 69 other conditions, according to our data. His top areas of expertise are Noonan Syndrome, RASopathies, Rommen Mueller Sybert Syndrome, and Marshall-Smith Syndrome.
University Of Gothenburg
Jovanna Dahlgren is in Goeteborg, Sweden. Dahlgren is rated as an Elite expert by MediFind in the treatment of Noonan Syndrome. She is also highly rated in 13 other conditions, according to our data. Her top areas of expertise are Noonan Syndrome, RASopathies, Pulmonary Valve Stenosis, and Pyruvate Dehydrogenase Deficiency.
Universidade De São Paulo
Debora Bertola is in Sao Paulo, Brazil. Bertola is rated as an Elite expert by MediFind in the treatment of Noonan Syndrome. She is also highly rated in 44 other conditions, according to our data. Her top areas of expertise are Rommen Mueller Sybert Syndrome, Noonan Syndrome, RASopathies, and Pycnodysostosis.
The Noonan Syndrome Foundation is a place where people dealing with this condition can find information and resources.
Complications may include:
- Abnormal bleeding or bruising
- Buildup of fluid in tissues of body (lymphedema, cystic hygroma)
- Failure to thrive in infants
- Leukemia and other cancers
- Low self-esteem
- Infertility in males if both testes are undescended
- Problems with the structure of the heart
- Short height
- Social problems due to physical symptoms
This condition may be found during early infant exams. A geneticist is often needed to diagnose Noonan syndrome.
Couples with a family history of Noonan syndrome may want to consider genetic counseling before having children.
Published Date: January 28, 2020
Published By: Anna C. Edens Hurst, MD, MS, Assistant Professor in Medical Genetics, The University of Alabama at Birmingham, Birmingham, AL. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
Cooke DW, Divall SA, Radovick S. Normal and aberrant growth in children. In: Melmed S, Auchus RJ, Goldfine AB, Koenig RJ, Rosen CJ, eds. Williams Textbook of Endocrinology. 14th ed. Philadelphia, PA: Elsevier; 2020:chap 25.
Madan-Khetarpal S, Arnold G. Genetic disorders and dysmorphic conditions. In: Zitelli BJ, McIntire SC, Nowalk AJ, eds. Zitelli and Davis' Atlas of Pediatric Physical Diagnosis. 7th ed. Philadelphia, PA: Elsevier; 2018:chap 1.
Mitchell AL. Congenital anomalies. In: Martin RJ, Fanaroff AA, Walsh MC, eds. Fanaroff and Martin's Neonatal-Perinatal Medicine. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 30.