Kantaputra mesomelic dysplasia: a second reported family.

We present the clinical and radiographic findings in a mother and son with a dominantly inherited mesomelic skeletal dysplasia almost identical to that described in a large Thai family by Kantaputra et al., in which ankle, carpal and tarsal synostoses were noted. The proband in the family is a 48-year-old woman with mesomelic limb shortening, most pronounced in the upper limbs. Her parents were of normal stature and build. Her 15-year-old son has similar mesomelic limb shortening, and in addition talipes equinovarus. Radiological examination showed severe shortening of the radius and ulna with bowing of the radius and dislocation of the radial head. Multiple carpal and tarsal synostoses were present and in addition, the talus and calcaneum were fused. In the original Thai family, linkage to chromosome 2q24-q32, which contains the HOXD cluster has been reported, and it is postulated that the phenotype may result from a disturbance of regulation of the HOXD cluster. Although linkage analysis was not possible in our family, molecular analysis was undertaken and HOXD11 was sequenced, however, no mutations were detected. This is only the second reported family affected with Kantaputra mesomelic dysplasia (MIM 156232), a distinct mesomelic skeletal dysplasia.