[Clinical and genetic analysis of a child with Noonan syndrome]

To identify potential mutation in a child clinically diagnosed as Noonan syndrome and to provide genetic counseling and prenatal diagnosis for his family.

Genomic DNA was extracted from peripheral blood samples of the patient and his parents, and amniotic fluid was taken from the mother during the second trimester. Next generation sequencing (NGS) was used to screen potential mutations from genomic DNA. Suspected mutation was verified by Sanger sequencing.

A heterozygous c.4A>G (p.Ser2Gly) mutation of the SHOC2 gene was identified in the patient but not among other family members including the fetus.

The Noonan syndrome is probably caused by the c.4A>G mutation of the SHOC2 gene. NGS is helpful for the diagnosis of complicated genetic diseases. SHOC2 gene mutation screening is recommended for patient suspected for Noonan syndrome.