© 2017, GENASSIST, Inc.     

By Keith S. Wexler, MBA, Maternal Fetal Medicine, Prenatal Diagnosis and Biotech/Life Sciences Consultant, GENASSIST, Inc.

Paul Wexler, M.D., F.A.C.O.G., Medical Director, GENASSIST, Inc.

Clinical Professor, Department of OB/GYN, University of Colorado Health Sciences Center

Clinical Professor, Division of Genetics/Dept. of Pediatrics, Univ. of Colorado/The Children’s Hospital


[*A recent study, that is ongoing, has suggested a possible relationship between maternal age (35 years or older) and/or paternal age (greater than 40 years) and autism and/or autism spectrum disorder(s) in a child. Reference: Israel & Mt. Sinai, NY.   *Some recent studies have suggested risk may be as high as 1:50 to 1:80.]



Noonan Syndrome is sometimes referred to as male Turner Syndrome.

Noonan Syndrome is often diagnosed at birth or in early childhood.

Noonan Syndrome findings are variable but may include:

  • Webbed neck
  • Cystic hygroma
  • Short stature
  • Widely spaced eyes (hypertelorism)
  • Low posterior hairline
  • Epicanthal folds
  • Posteriorly rotated low set ears
  • Kyphoscoliosis
  • Pectus excavatum
  • Heart defects (often pulmonary stenosis and/or hypertrophic cardiomyopathy)
  • Blood disorders

Noonan Syndrome is inherited in an autosomal dominant manner and mutations in multiple genes have been described. *Up to 50% of individuals with Noonan Syndrome have a new mutation which causes the syndrome.

*Prenatal diagnosis may be an option if the mutation is known. Up to 25% of individual with Noonan Syndrome will Not be diagnosed with molecular testing.

The remainder of Noonan Syndrome cases are inherited from a parent who may manifest more severe or milder findings.

Males are more commonly affected than females.

Up to 1/3 of individuals with Noonan Syndrome may have problems suggestive of Austistic-like behaviors including:

  • Speech problems
  • Motor problems
  • Hearing loss
  • Attention problems
  • Learning problems

Analysis: As we head forward in the brave new world of Microarray and/or High Resolution Chromosomal Microarray Analysis (CMA) screening, we will be performing more problem focused amniocentesis, rather than amniocentesis traditionally based upon a mother’s maternal age related risk.

As with any screening test, women of all ages who are detected as being carriers for rare diseases will have the weigh the risks, benefits and limitations of invasive testing