Fig. 5

The MYH2 gene and protein. A Schematic illustration of the coding and noncoding regions of the MYH2 (NM_017534.6), including the novel splice-site variant identified in this study (in red, c.5673 + 1G > C) and previously reported variants. A schematic illustration of the MyHC IIa protein shows the borders between the myosin head and tail domains as well as the assembly competence domain. B Human skeletal muscle MyHC isoforms show marked homology. The assembly competence domain (ACD, 29 residues) is marked in red. The aberrant splicing due to the c.5673 + 1G > C variant results in transcript lacking exon 39. These transcripts have a disrupted assembly competence domain by lack of 15 residues of the domain (aa1877–1891). The two other described dominant variants located in this region are marked in bold (c.5609 T > C; p.L1870P and c.5630 T > C; p.L1877P). For MYH7, three amino acids causing myosin storage myopathy are marked in blue. One of these is located in the middle of the ACD