Rhizomelic chondrodysplasia punctata (RCDP) is an autosomal recessive peroxisomal disorder characterized by disproportionate short stature with rhizomelic limb shortening, congenital cataracts, distinct facial features, severe intellectual disability, and seizures. Radiographs of infants with RCDP show punctate calcifications in the epiphyseal cartilage and coronal clefts of the vertebral bodies. The punctate calcifications generally resolve by one year of age leaving abnormal epiphyses and flared, irregular metaphyses. Most individuals with classic RCDP do not survive the first decade of life; however, a few individuals with a milder form of RCDP have been described. These individuals have congenital cataracts, mild epiphyseal changes, less severe intellectual disability and growth deficiency, and some do not have rhizomelia. RCDP1 (MIM 215100) is caused by mutations in PEX7, which encodes peroxisome biogenesis factor 7, a protein involved in the transport of peroxisomal enzymes to the peroxisome.  RCDP2 (MIM 222765) and  RCDP3 (MIM 600121) are caused by mutations in GNPAT and AGPS, respectively. GNPAT codes for dihydroxyacetonephosphate acyltransferase and AGPS codes for alkylglyceronephosphate synthase. More than 90% of patients with RCDP have defects in PEX7 and less than 10% have mutations either in GNPAT or AGPS.