New Mutations in NEB Gene Discovered by Targeted Next-Generation Sequencing in Nemaline Myopathy Italian Patients

• Published in: Journal of molecular neuroscience Vol. 59; no. 3; pp. 351 - 359
• Main Authors: Piga, Daniela, Magri, Francesca, Ronchi, Dario, Corti, Stefania, Cassandrini, Denise, Mercuri, Eugenio, Tasca, Giorgio, Bertini, Enrico, Fattori, Fabiana, Toscano, Antonio, Messina, Sonia, Moroni, Isabella, Mora, Marina, Moggio, Maurizio, Colombo, Irene, Giugliano, Teresa, Pane, Marika, Fiorillo, Chiara, D’Amico, Adele, Bruno, Claudio, Nigro, Vincenzo, Bresolin, Nereo, Comi, Giacomo Pietro
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.07.2016; Springer Nature B.V
• Subjects: Biomedical and Life Sciences; Biomedicine; Biopsy; Cell Biology; Child; Copy number; Cost analysis; DNA Copy Number Variations; Gene sequencing; Genetic analysis; Genetic counseling; Genetic screening; Genetic Testing - methods; Heterozygote; High-Throughput Nucleotide Sequencing - methods; Humans; Infant; Introns; Muscle Proteins - genetics; Mutation; Myopathies, Nemaline - genetics; Myopathies, Nemaline - pathology; Myopathy; Nemaline myopathy; Neurochemistry; Neurology; Neuromuscular diseases; Neurosciences; Next-generation sequencing; Patients; Promoter Regions, Genetic; Proteomics; Ribonucleic acid; RNA; Sequence Analysis, DNA - methods; Transcription; Young Adult; Nemaline myopathy; mutations; Next-generation sequencing; NEB mutations
• ISSN: 0895-8696; 1559-1166
• DOI: 10.1007/s12031-016-0739-2

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.