Like his brother Tim, Jon suffers from hereditary multiple exostoses.

It is associated with hereditary multiple exostoses.

Bone dysplasias, including Paget's disease, fibrous dysplasia, enchondromatosis, and hereditary multiple exostoses, increase the risk of osteosarcoma.

Hereditary multiple exostoses (HME)

Hereditary Multiple Exostoses (HME)

Hereditary multiple exostoses is inherited as an autosomal dominant genetic condition and is associated with abnormalities (mutations) in the EXT1 and EXT 2 genes.

PGD is also now being performed in a disease called Hereditary multiple exostoses (MHE/MO/HME).

Examples of this type of disorder are Huntington's disease, neurofibromatosis type 1, neurofibromatosis type 2, Marfan syndrome, hereditary nonpolyposis colorectal cancer, and hereditary multiple exostoses, which is a highly penetrant autosomal dominant disorder.

Hereditary multiple exostoses (HME or MHE), also known as Diaphyseal aclasis, is a rare medical condition in which multiple bony spurs or lumps (also known as exostoses, or osteochondromas) develop on the bones of a child.

Metachondromatosis demonstrates autosomal-dominant transmission and presents with both multiple osteochondromas and enchondromas.