We report a 7-year-old patient with chondrodysplasia punctata but with
out rhizomelia. He was born with typical clinical and radiological sym
ptoms of this disease. He developed slowly with considerable psychomot
or retardation but improved later, gaining some speech and psychosocia
l contacts. Joint contractures and bilateral cataracts are still major
problems. De novo plasmalogen synthesis in fibroblasts was greatly re
duced and DHAP-AT activity was at the lower limit of controls. Peroxis
omal thiolase was present in its precursor form only. Membrane fluidit
y (measured by TMA-DPH fluorescence anisotropy) was increased in eryth
rocyte ghosts and in lymphocytes. Plasma phytanic acid concentration w
as elevated 5-fold. The patient represents a mild clinical course of c
hondrodysplasia punctata, resembling Conradi-Hunermann syndrome, but b
iochemically he has the typical peroxisomal dysfunction of rhizomelic
chondrodysplasia punctata except for a high residual activity of DHAP-
AT.