Mucolipidosis type IV (MLIV) constitutes the most direct link between defective lysosomal Ca2+ release and neurodegeneration, caused by dysfunction of the lysosomal cation channel TRPML1 (also called MCOLN1) (Slaugenhaupt, 2002; Feng & Yang, 2016). This evidence concerns the gene MCOLN1 and mucolipidosis type IV.