Abstract
Nemaline myopathy represents a group of clinically and genetically heterogeneous neuromuscular disorders. Different clinical-genetic entities have been characterized in the last few years, with implications for diagnostics and genetic counseling. Fifty percent of nemaline myopathy forms are due to NEB mutations, but genetic analysis of this large and complex gene by Sanger sequencing is time consuming and expensive. We selected 10 Italian patients with clinical and biopsy features suggestive for nemaline myopathy and negative for ACTA1, TPM2 and TPM3 mutations. We applied a targeted next-generation sequencing strategy designed to analyse NEB coding regions, the relative full introns and the promoter. We also evaluated copy number variations (by CGH array) and transcriptional changes by RNA Sanger sequencing, whenever possible. This combined strategy revealed 11 likely pathogenic variants in 8 of 10 patients. The molecular diagnosis was fully achieved in 3 of 8 patients, while only one heterozygous mutation was observed in 5 subjects. This approach revealed to be a fast and cost-effective way to analyse the large NEB gene in a small group of patients and might be promising for the detection of pathological variants of other genes featuring large coding regions and lacking mutational hotspots.
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Acknowledgments
This research received funding from Telethon Grant GUP08005. The Telethon Genetic Biobanks Network GTB07001E provided the DNA used in this study.
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Patient data were completely anonymised and summarised in tables. They are not accompanied by patient pictures and clinical or personal details that can reveal the patient’s identity.
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Since the study is multicentric, each centre collected written informed consent for research purposes from each patient according to the guidelines of the local ethical committee.
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Piga, D., Magri, F., Ronchi, D. et al. New Mutations in NEB Gene Discovered by Targeted Next-Generation Sequencing in Nemaline Myopathy Italian Patients. J Mol Neurosci 59, 351–359 (2016). https://doi.org/10.1007/s12031-016-0739-2
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DOI: https://doi.org/10.1007/s12031-016-0739-2