Chondrodysplasia punctata with a mild clinical course

We report a 7-year-old patient with chondrodysplasia punctata but without rhizomelia. He was born with typical clinical and radiological symptoms of this disease. He developed slowly with considerable psychomotor retardation but improved later, gaining some speech and psychosocial contacts. Joint contractures and bilateral cataracts are still major problems. De novo plasmalogen synthesis in fibroblasts was greatly reduced and DHAP-AT activity was at the lower limit of controls. Peroxisomal thiolase was present in its precursor form only. Membrane fluidity (measured by TMA-DPH fluorescence anisotropy) was increased in erythrocyte ghosts and in lymphocytes. Plasma phytanic acid concentration was elevated 5-fold. The patient represents a mild clinical course of chondrodysplasia punctata, resembling Conradi-Hünermann syndrome, but biochemically he has the typical peroxisomal dysfunction of rhizomelic chondrodysplasia punctata except for a high residual activity of DHAP-AT