The phenotypic variability of diastrophic dysplasia.

To determine the relationship between so-called "diastrophic variant" and diastrophic dysplasia, four patients considered to have the variant condition were studied in detail and compared to 67 patients (including 17 sets of affected sibs) considered to have classical diastrophic dysplasia. Analysis of the combined clinical, radiographic, histologic, and genetic data indicates that there is wide variability in the phenotypic expression of diastrophic dysplasia, even within sibships, and that those individuals previously labeled as having "diastrophic variant" appear to have mild diastrophic dysplasia.