Analysis of the PTPN11 gene in idiopathic short stature children and Noonan syndrome patients

Background Mutations in the PTPN11 gene are the main cause of Noonan syndrome (NS). The presence of some NS features is a frequent finding in children with idiopathic short stature (ISS). These children can represent the milder end of the NS clinical spectrum and PTPN11 is a good candidate for involvement in the pathogenesis of ISS. Objective To evaluate the presence of mutations in PTPN11 in ISS children who presented NS-related signs and in well-characterized NS patients. Patients and methods We studied 50 ISS children who presented at least two NS-associated signs but did not fulfil the criteria for NS diagnosis. Forty-nine NS patients diagnosed by the criteria of van der Burgt et al. were used to assess the adequacy of these criteria to select patients for PTPN11 mutation screening. The coding region of PTPN11 was amplified by polymerase chain reaction (PCR), followed by direct sequencing. Results No mutations or polymorphisms were found in the coding region of the PTPN11 gene in ISS children. Nineteen of the 49 NS patients (39%) presented mutations in PTPN11. No single characteristic enabled us to distinguish between NS patients with or without PTPN11 mutations. Conclusion Considering that no mutations were found in the present cohort with NS-related signs, it is unlikely that mutations would be found in unselected ISS children. The van der Burgt et al. criteria are adequate in attaining NS diagnosis and selecting patients for molecular studies. Mutations in the PTPN11 gene are commonly involved in the pathogenesis of NS but are not a common cause of ISS.

Behavioral disturbances in Noonan Syndrome: Brazilian preliminary data

Different from other countries Of Europe and North American, studies about the behavioral profile of Noonan syndrome`s patients are inexistent. The objective of this study was to report the profiles of behavioral functions of 10 participants (4 females and 6 males), with mutations in the PTPN11 gene. For this assessment it was used the Inventory of Behaviors of Children and Adolescents from 6 to 18 years (CBCL/6-18) and the Inventory of Auto-Evaluation for Adults from 18 to 59 years (ASR). The main results point that in Adaptive Functioning Scale all the participants were in the normality range. In the Syndrome Scale the adult participants were in normality range and the children were in clinical range to the sub-scales anxious/depressed, somatic complaints and aggressive behavior. In the DSM-Oriented Scale, 25% of the adult patients were in the borderline clinical range and clinical range, respectively, for Avoidant Personality Problems and Antisocial Personality Problems. About the both children in this scale were in the clinical range of Affective Problems and Anxiety Problems. This relatively homogenous sample, regarding the PTPN11 gene, shows a normal adult behavioral profile, on the average. However, the individual children anti adult profiles show diverse internalizing and externalizing behavioral disturbances.