IDS and mucopolysaccharidosis: They also manifest in other forms of mucopolysaccharidosis (MPS) characterized by defective metabolism of HS, such as MPS-II and MPS-I, caused by disruptions to the enzymes iduronate-2-sulfatase and α-L-iduronidase, respectively, which leads to accumulation of HS and other GAGs; for this reason, these diseases are accompanied by a faster shift from autistic- to dementia-like symptoms, meaning autistic-like symptoms can be harder to detect5,6.