PSAP (Prosaposin): PSAP is a precursor protein that is cleaved into saposins, which are essential for the normal breakdown of lipids in lysosomes. Deficiencies in saposins can lead to various lysosomal storage disorders, characterized by the accumulation of complex lipids in cells. PSAP mutations are linked to conditions like Gaucher disease, Fabry disease, and metachromatic leukodystrophy....