AR-MED (rMED) can result from homozygosity or compound heterozygosity for mutations in the gene encoding SLC26A2 (EDM4; MIM# 226900) [Hastbacka et al., 1999; Rossi and Superti-Furga, 2001; Superti-Furga et al., 1999] and is the mild end of the phenotypic spectrum that includes achondrogenesis 1B and diastrophic dysplasia [Rossi and Superi-Furga, 2001]. This evidence concerns the gene SLC26A2 and diastrophic dysplasia.