Dyggve-Melchior-Clausen (DMC) syndrome is a rare, progressive genetic condition characterized by abnormal skeletal development, microcephaly, and intellectual disability. Only about 100 cases have been reported to date. Skeletal abnormalities may include a barrel-shaped chest with a short trunk, partial dislocation of the hips, knock knees, bowlegs, and decreased joint mobility. A small number of affected individuals experience instability in the upper neck vertebrae that can lead to spinal cord compression, weakness and paralysis. Normally, there is growth deficiency resulting in short stature. DMC is caused by genetic changes in the DYM gene and is inherited in an autosomal recessive manner.