Lecithin:cholesterol acyltransferase deficiency: identification of a causative gene mutation and a co-inherited protein polymorphism.

We have recreated and expressed two known natural mutations within the LCAT gene which were reported on both alleles in a single case of familial LCAT deficiency. We demonstrate that the Ala-93-->Thr mutation is responsible for the biochemical defect while the Arg-158-->Cys mutation is a co-inherited natural polymorphism of LCAT which results in normal enzyme function.