We have located links that may give you full text access.
Noonan syndrome: comparing mutation-positive with mutation-negative dutch patients.
Molecular Syndromology 2013 June
Noonan syndrome (NS) is an autosomal dominant disorder characterized by facial dysmorphisms, short stature and congenital heart defects. The disorder is genetically heterogeneous and shows clinical overlap with other RASopathies. These syndromes are caused by mutations in a variety of genes leading to dysregulation of the RAS-MAPK pathway: PTPN11, KRAS, SOS1, RAF1, CBL, SHOC2, NRAS, BRAF, MAP2K1, MAP2K2, HRAS, NF1 and SPRED1. In this study, we conduct a genotype-phenotype analysis of 33 patients with a clinical diagnosis of NS without a PTPN11 mutation. Mutation analysis of the genes involved in RASopathies was performed, except for NF1 and SPRED1. In 14 (42%) NS patients, a mutation was found, 7 (21%) had a mutation in SOS1, 3 (9%) in RAF1 and 1 (3%) in KRAS, MAP2K2, BRAF and SHOC2 each. The phenotype of these mutation-positive cases corresponded to that described in the literature. In the cases with a BRAF and MAP2K2 mutation, the diagnosis cardio-facio-cutaneous syndrome was made. The patient with the SHOC2 mutation had features compatible with 'Noonan-like syndrome with loose anagen hair'. Three major clinical features of NS - a typical face, short stature and a pulmonary valve stenosis - were less frequently present in the group without a mutation. Missense mutations in genes encoding proteins of the RAS-MAPK pathway cause NS. The 3 major clinical features of NS were less frequently present in the mutation-negative patients, which stresses the importance of the syndrome-specific symptoms of the face, heart and short stature in NS. However, all mutation-negative cases met the NS criteria, indicating that the involvement of novel genes is to be expected.
Full text links
Related Resources
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app