Ege University Faculty of Medicine, Department of Medical Genetics, İzmir, Turkey**
Bezmialem Vakıf University Faculty of Medicine, Department of Medical Genetics, İstanbul, Turkey***
Dr. Behçet Uz Children’s Hospital, Clinic of Medical Genetics, İzmir, Turkey****
Kayseri Training and Research Hospital, Clinic of Medical Genetics, Kayseri, Turkey*****
İstanbul University Cerrahpaşa Faculty of Medicine, Department of Pediatric Genetics, İstanbul, Turkey******
Erciyes University Faculty of Medicine, Department of Medical Genetics, Kayseri, Turkey
Craniosynostosis, premature closure of one or more cranial sutures, may occur in both non-syndromic and syndromic forms. Birth prevalence of craniosynostosis is 1/ 2,100–1/2,500. FGFR2, FGFR3, FGFR1, TWIST1, and EFNB1 genes play a role in the syndromic craniosynostosis presenting with craniofacial abnormalities, including hypertelorism, proptosis, and midfacial hypoplasia. Limb, cardiac, central nervous system, and tracheal malformations have also been described. Mutations in the FGFR2 gene located on 10q26 that encode fibroblast growth factor receptor 2 is responsible for a part of the syndromic craniosynostosis. The aim of this study was to determine FGFR2 gene mutations in 85 craniosynostosis cases including Apert, Pfeiffer, and Crouzon syndromes, and isolated craniosynostosis patients who were referred to molecular genetics laboratory of Medical Genetics Department, Ege University between 2010 and 2016.
Sequence analysis was performed on 2 exons (exons 7-8) of the FGFR2 gene in 85 cases referred for pre-diagnosis of craniosynostosis between 2010 and 2016. Sanger sequencing analysis method was used for sequence analysis.
Mutations were detected in twenty of the cases (23%). The frequency of FGFR2 mutation in this study was 20% S252W and P253R (4 cases), 15% Y382C (3 cases), 10% Y308C (2 cases) and 5% A314S, A266P, P253A, W290C, W290R, S351C, S252P (1 case).
In syndromic and isolated craniosynostosis patients, the analysis of exons 7 and 8, which is one of the mutational hot spot of FGFR2 gene, allows diagnosis in 23% of patients. It has been concluded that performing complete FGFR2 gene analysis will provide larger numbers of molecular diagnosis.