GeneDx :: Tests :: Noonan Syndrome - Prenatal Testing based on ultrasound findings

301-519-2100 • FAX 301-519-2892 • 207 PERRY PARKWAY GAITHERSBURG, MD 20877

Noonan Syndrome - Prenatal Testing based on ultrasound findings

PTPN11
RAF1
SOS1
KRAS
BRAF
HRAS
MAP2K1
MAP2K2
SHOC2

In fetuses, transient first trimester cystic hygroma has been associated with a clinical diagnosis of Noonan syndrome in 1-4% of cases with normal karyotype. In a recent retrospective study of 134 fetuses with sonographic findings suggestive of Noonan syndrome, including data from GeneDx and Mount Sinai School of Medicine, 9% (12 fetuses) were found to have a heterozygous missense mutation in PTPN11. The prevalence of PTPN11 mutations was higher in fetuses with cystic hygroma associated with additional abnormalities (24%), in particular with congenital heart defects (37%). The mutation detection rate for the BRAF, HRAS, KRAS, MAP2K1, MAP2K2, RAF1, SHOC2, and SOS1 genes has not yet been established.

We offer a Comprehensive Prenatal Noonan Syndrome Panel Panel using a GeneDx custom-designed resequencing array including all 8 genes currently known to cause Noonan syndrome or related disorders (BRAF, HRAS, KRAS, MAP2K1, MAP2K2, PTPN11, RAF1, and SOS1). This panel also includes mutation specific analysis for the Ser2Gly SHOC2 gene mutation using bi-directional DNA sequencing.

Prenatal testing is performed on genomic DNA obtained from chorionic villi, cultured villi or cultured amniocytes. In all cases a maternal sample (either whole blood in EDTA or buccal brushes) should accompany the fetal sample for maternal cell contamination studies.

Information Sheet, including prices and CPT codes
Consent Document
Genetic Test Sample Submission Form (Test Requisition Form) including Payment Options