Aims
To determine the clinical and molecular genetic characteristics of Turkish patients with neurofibromatosis type 1. Study design: Cross-sectional study.
Background
Neurofibromatosis type 1 (NF1) is a neurocutaneous disorder that
Conclusion
The novel pathogenic variants identified in this study broaden the spectrum of pathogenic variants in NF1 and provide better clinical characterization of NF1. RNA-seq experiments are recommended in patients who meet the National Institutes of Health diagnostic criteria for NF but have not identified any variants in nextgeneration sequencing, multiplex ligation-dependent probe amplification, or array-comparative genomic hybridization analysis.
Methods
For the genetic analysis of 27 Turkish families clinically diagnosed with NF1 between 1990 and 2019, we used a multi-step process consisting of next-generation sequencing, multiplex ligation-dependent probe amplification, and array-comparative genomic hybridization.
Results
In this study, we identified 11 novel and 11 previously reported single-nucleotide variants in 22 families. Whole gene deletions were detected by multiplex ligation-dependent probe amplification analysis in 3 families. Of those, array comparative genomic hybridization analysis defined a 17q11.2 deletion in 4 patients from 2 families and 1.2-Mb involving 1 unrelated patient. All patients with a deletion had facial dysmorphism, suggesting a peculiar phenotype in this group. We could not find any pathogenic variant in the 2 families that met the National Institutes of Health criteria.