The mucopolysaccharidoses (MPS) are a family of lysosomal storage diseases wherein patients have an inability to properly metabolize glycosaminoglycan’s (GAGs) resulting in toxic accumulation of undigested dermatan sulfate (DS), heparan sulfate (HS) and/or keratin sulfate (KS) in the lysosome. The gene discussed is MAP3K14; the disease is mucopolysaccharidosis.