Multiple epiphyseal dysplasia (MED; EDM1, OMIM 132400; EDM2, OMIM 600204; EDM3, OMIM 600969; EDM4, OMIM 226900; EDM5, OMIM 607078; EDM6, OMIM 614135) is an autosomal dominant inherited disease of the skeletal system, characterized by mild short stature and early-onset degenerative joint disease, caused by heterogeneous genotypes involving more than six genes ( COMP , COL9A1 , COL9A2 , COL9A3 , MATN3 , DTDST ).[sup] However, in approximately 10–20% of all samples analyzed, a mutation cannot be identified in any of the six genes mentioned above, suggesting that the presence of other unidentified causative genes is also involved in the pathogenesis of MED.[sup]
The COMP associated with EDM1 is the most common form of MED, accounting for at least half of the cases.[sup] MED usually presents with pain in the hips and/or knees after exercise, small height, relatively short limbs in comparison with a normal trunk, pain, and progression of joint deformity.