Fatty Alcohol Accumulation in the Autosomal Recessive Form of Rhizomelic Chondrodysplasia Punctata

Patients with the autosomal recessive form of rhizometic chondrodysplasia punctata (ARRCDP) and other generalized peroxisomal disorders are deficient in the incorporation of fatty alcohol into plasmalogen lipids. To determine whether these patients accumulated fatty alcohol, we measured their plasma fatty alcohol concentrations. Plasma octadecanol levels were elevated in six patients with AR-RCDP but tended to be normal in other generalized peroxisomal disorders such as neonatal adrenoleukodystrophy and Zellweger syndrome. Cultured skin fibroblasts from AR-RCDP patients accumulated six-fold more hexadecanol than normal when cells were incubated in the presence of palmitate but had normal hexadecanol content when palmitate was not present in the culture medium. These cells were profoundly deficient in the incorporation of hexadecanol into ether lipids but oxidized hexadecanol to fatty acid normally. AR-RCDP fibroblasts also showed a two- to seven-fold increase in the rate of hexadecanol synthesis, which was associated with an increase in the activity of acyl-CoA reductase. We conclude that patients with AR-RCDP accumulate fatty alcohol due to its impaired incorporation into ether lipids and a greatly increased rate of fatty alcohol synthesis.