SLC26A2 and diastrophic dysplasia: In addition, the SLC26A2 gene which mediates sulfate transport into chondrocytes for the sulfonation of chondroitin proteoglycan, is linked to four types of chondrodysplasias: multiple epiphyseal dysplasia (MEM), diastrophic dysplasia (DTD), atelosteogenesis Type II (AO2) and achondrogenesis Type IB (ACG1B) [14].