Neurofibromatosis Type 1 Molecular Diagnosis in Turkish Patients

Abstract

Neurofibromatosis type 1 (NF1) is a rare autosomal dominant, hereditary tumor-predisposition disorder.  NF1 is characterized by multiple cafe-au-lait spots, multiple cutaneous neurofibromas, freckling in the axilla and inguinal area and iris Lish nodules. The prevalence is approximately 1 in 3000 individuals worldwide. In the present study, we aimed to detect the NF1 gene alterations in Turkish NF1 patients using next-generation sequencing (NGS). We analyzed 47 patients for mutations and all of them were unrelated. 27 NF1 mutations were identified. In total, 25 of the 27 mutations were likely pathogenic or pathogenic according to the ACMG criteria. Five of the pathogenic or likely pathogenic variants were novel. This is one of the large NF1 genetic  studies in Turkey. We did not determine a genotype-phenotype correlation in this study because of the highly variable expressivity of the NF1 gene. According to our findings each population may have several exon regions that contain recurrent mutations. We suggest that genetic analysis with next-generation tools are more useful and helpful to provide early diagnosis and genetic counseling.