A Novel COMP Gene Mutation in a Korean Kindred with Multiple Epiphyseal Dysplasia

ABSTRACT

Multiple epiphyseal dysplasia (MED) is a clinically and genetically heterogeneous chondroplasia, characterized by delayed development of the ossification centers and, deformities of the extremities that involve only the epiphysis and result in mild short stature. Mutations in the cartilage oligomeric matrix protein (COMP) gene are most commonly found, and most of the mutations are located in the calmodulin-like repeats and the C-terminal domain. We report a Korean kindred of?12 family members with MED in four generations who were found to have a novel mutation in the COMP gene. A pedigree showed early onset osteoarthritis requiring arthroplasty that was an autosomal dominant inherited trait. Radiological examinations demonstrated the presence of osteochondral defects in the medial femoral condyles, and the knee and hip joints showed variable degrees of precocious degenerative changes. Mutation analysis of the COMP gene in the proband and five other affected family members identified a novel missense mutation, c.1280G>C (p.Gly427Ala) in exon 12, which was not found in three unaffected family members. Direct sequencing of the COMP gene may yield pathogenic mutations in dominantly inherited MED cases, and may provide opportunities of carrier detection among high-risk family members, leading to genetic counseling for early diagnosis and intervention before the onset of complications.