MCOLN1 and mucolipidosis type IV: The application of FRASER for reanalysis of RNA‐seq data led to the identification of intron retention in the MCOLN1 gene, encoding the mucolipin 1 protein, thereby confirming the diagnosis of a lysosomal storage disorder: mucolipidosis type IV, in a suspected mitochondrial disease case that had been exhaustively investigated [54, 75].