Abstract Hereditary multiple exostoses (HME) is a rare skeletal disorder characterized by the formation of multiple benign cartilage-capped tumors, usually in the metaphyseal region of the long bones.
Exotosin (EXT) proteins are involved in the chain elongation step of heparan sulfate (HS) biosynthesis, which is intricately involved in organ development. Loss of function mutations (LOF) in EXT1 and
