Furthermore, in human fibroblasts derived from MLIV patients, there was an impairment in the autophagic pathway, which induced a significant accumulation of autophagic markers p62 (SQSTM1/p62) and LC3-II (1A/1B light chain 3-phosphatidyl ethanolamine conjugate), as a result of increased autophagosome formation and delayed autophagosome fusion with lysosomes. The gene discussed is SQSTM1; the disease is mucolipidosis type IV.