Background  Multiple epiphysis dysplasia (MED) is a common skeletal dysplasia with a significant locus heterogeneity. In the majority of clinically defined cases, mutations have been identified in the gene encoding cartilage algometric matrix protein (COMP).

Methods  Five patients were included in the study. Linkage analysis and mutation analysis of the COMP gene were conducted in the patients and their family members.

Results  We have identified a novel mutation in axon 14 of COMP gene in the family.

Conclusions  This mutation produced a severe MED phenotype with marked short stature, early onset osteoarthritis, and remarkable radiographic changes. Our results extended the range of disease-causing mutations in COMP gene and contributed more information about relationship between mutations and phenotype.