The first PTPN11 mutations in hotspot exons reported in Moroccan children with Noonan syndrome and comparison of mutation rate to the previous studies

Conclusion: The present study allowed identification of mutations clustered in exons 3 and 8 of the PTPN11 gene in a Moroccan Noonan syndrome cohort and enabled us to give appropriate genetic counseling to the mutation-positive patients.

📌 3 Key Takeaways

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Objective & Hypothesis:Background/aim: Noonan syndrome is an autosomal dominant disorder with an incidence of 1/1000?2500.

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Key Findings & Data:It results from protein-tyrosine phosphatase, nonreceptor type 11 (PTPN11) mutations in roughly 50% of cases.

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Conclusion & Impact:Conclusion: The present study allowed identification of mutations clustered in exons 3 and 8 of the PTPN11 gene in a Moroccan Noonan syndrome cohort and enabled us to give appropriate genetic counseling to the mutation-positive patients.

🔬Design:Research Article

📍Scope:Comprehensive Sample

⚙️Variables:Noonan syndrome · PTPN11 · mutation analysis

Abstract

Background/aim: Noonan syndrome is an autosomal dominant disorder with an incidence of 1/1000?2500. It results from protein-tyrosine phosphatase, nonreceptor type 11 (PTPN11) mutations in roughly 50% of cases. Mutational screening of PTPN11 has been carried out in different populations. Thus, the aim of this study was to screen, for the first time, PTPN11 mutations in a series of Moroccan Noonan syndrome patients. Materials and methods: We used bidirectional sequencing of exons 3 and 8, considered as PTPN11 mutation hot spots, and then compared the rate of mutational events of these exons between different populations using chi-square and Fisher?s exact tests. Results: We detected 3 heterozygous mutations (Asp61Gly, Tyr63Cys, and Asn308Ser) in 4 individuals of 16 sporadic patients (25%). The rate of mutation in our cohort did not differ from that of other populations. However, we found significant differences in the mutation rate of exon 8 between one Japanese cohort and some populations, which requires more investigations to be explained. Conclusion: The present study allowed identification of mutations clustered in exons 3 and 8 of the PTPN11 gene in a Moroccan Noonan syndrome cohort and enabled us to give appropriate genetic counseling to the mutation-positive patients.

Özet

Background/aim: Noonan syndrome is an autosomal dominant disorder with an incidence of 1/1000?2500. It results from protein-tyrosine phosphatase, nonreceptor type 11 (PTPN11) mutations in roughly 50% of cases. Mutational screening of PTPN11 has been carried out in different populations. Thus, the aim of this study was to screen, for the first time, PTPN11 mutations in a series of Moroccan Noonan syndrome patients. Materials and methods: We used bidirectional sequencing of exons 3 and 8, considered as PTPN11 mutation hot spots, and then compared the rate of mutational events of these exons between different populations using chi-square and Fisher?s exact tests. Results: We detected 3 heterozygous mutations (Asp61Gly, Tyr63Cys, and Asn308Ser) in 4 individuals of 16 sporadic patients (25%). The rate of mutation in our cohort did not differ from that of other populations. However, we found significant differences in the mutation rate of exon 8 between one Japanese cohort and some populations, which requires more investigations to be explained. Conclusion: The present study allowed identification of mutations clustered in exons 3 and 8 of the PTPN11 gene in a Moroccan Noonan syndrome cohort and enabled us to give appropriate genetic counseling to the mutation-positive patients.

Keywords

Noonan syndrome PTPN11 mutation analysis SHP-2 mutation rate comparison

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Cite This Article

BOUCHIKHI, I. E., SAMRI, I., HOUSSAINI, M. I., TRHANINT, S., BOUGUENOUCH, L., SAYEL, H., HIDA, M., ATMANI, S., OULDIM, K. (2015). The first PTPN11 mutations in hotspot exons reported in Moroccan children with Noonan syndrome and comparison of mutation rate to the previous studies. Turkish Journal of Medical Sciences, Cilt: 45 - Sayı: 2, 306–312. https://ajindex.com/articles/113995

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