Targeted massively parallel sequencing and histological assessment of skeletal muscles for the molecular diagnosis of inherited muscle disorders

J Med Genet. 2017 Feb;54(2):104-110. doi: 10.1136/jmedgenet-2016-104073. Epub 2016 Sep 6.

Abstract

Background: Inherited skeletal muscle diseases are genetically heterogeneous diseases caused by mutations in more than 150 genes. This has made it challenging to establish a high-throughput screening method for identifying causative gene mutations in clinical practice.

Aim: In the present study, we developed a useful method for screening gene mutations associated with the pathogenesis of skeletal muscle diseases.

Methods: We established four target gene panels, each covering all exonic and flanking regions of genes involved in the pathogenesis of the following muscle diseases: (1) muscular dystrophy (MD), (2) congenital myopathy/congenital myasthenic syndrome, (3) metabolic myopathy and (4) myopathy with protein aggregations/rimmed vacuoles. We assigned one panel to each patient based on the results of clinical and histological analyses of biopsied muscle samples and performed high-throughput sequencing by using Ion PGM next-generation sequencer. We also performed protein analysis to confirm defective proteins in patients with major muscular dystrophies. Further, we performed muscle-derived cDNA analysis to identify splice-site mutations.

Results: We identified possible causative gene mutations in 33% of patients (62/188) included in this study. Our results showed that the MD panel was the most useful, with a diagnostic rate of 46.2%.

Conclusions: Thus, we developed a high-throughput sequencing technique for diagnosing inherited muscle diseases. The use of this technique along with histological and protein analyses may be useful and cost-effective for screening mutations in patients with inherited skeletal muscle diseases.

Keywords: Muscle pathology; Muscular dystrophy; Myopathy; Next-generation sequencing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Distal Myopathies / diagnosis
  • Distal Myopathies / genetics*
  • Distal Myopathies / pathology
  • Exons / genetics
  • Female
  • High-Throughput Nucleotide Sequencing*
  • High-Throughput Screening Assays
  • Humans
  • Male
  • Muscle, Skeletal / pathology
  • Muscular Diseases / diagnosis
  • Muscular Diseases / genetics*
  • Muscular Diseases / pathology
  • Muscular Dystrophies / diagnosis
  • Muscular Dystrophies / genetics*
  • Muscular Dystrophies / pathology
  • Mutation
  • Myasthenic Syndromes, Congenital / diagnosis
  • Myasthenic Syndromes, Congenital / genetics*
  • Myasthenic Syndromes, Congenital / pathology
  • Protein Aggregation, Pathological / genetics

Supplementary concepts

  • Distal myopathy, Nonaka type