Mild variable Noonan syndrome in a family with a novel PTPN11 mutation.
Noonan syndrome (OMIM 163950) is a common genetic condition with variable clinical expression and genetic heterogeneity. About half of the cases can be accounted to activating mutations in the PTPN11 gene encoding SHP-2. We report on a family with mild, variable expression of Noonan syndrome in five individuals. Clinical manifestations included short stature, craniofacial anomalies and thorax deformity, but none of the affected family members had a heart defect. Sequencing of the entire coding region of PTPN11 revealed a novel mutation c.1226G-->C in exon 11 predicting the amino acid exchange G409A. This mutation is not located in the previously known mutation clusters. Our observation and the recent report of a mutation affecting a neighbouring residue (T411M) in a family with a variable phenotype suggest that mutations in this particular region of SHP-2 may have effects on the protein that differ from those of the classical mutations.
Zenker
Martin
M
Institute of Human Genetics, University of Erlangen--Nuremberg, Schwabachanlage 10, 91054 Erlangen, Germany. mzenker@humgenet.uni-erlangen.de
Voss
Egbert
E
Reis
André
A
D000595:Amino Acid Sequence; D019943:Amino Acid Substitution / Q000235:genetics*; D002648:Child; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D009634:Noonan Syndrome / Q000235:genetics* / Q000473:pathology*; D017354:Point Mutation; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D017027:Protein Tyrosine Phosphatases / Q000235:genetics*
D047908:Intracellular Signaling Peptides and Proteins; C516724:PTPN11 protein, human; D054592:Protein Tyrosine Phosphatase, Non-Receptor Type 11; D017027:Protein Tyrosine Phosphatases