Lecithin: cholesterol acyltransferase activity and fatty acid composition of erythrocyte phospholipids in Friedreich's ataxia.

In a study of the fatty acid composition of erythrocyte membrane phospholipids in Friedreich's ataxia, a lower percentage of linoleic acid in phosphatidylcholine was demonstrated. An enzyme involving the exchange of lipids between plasma and erythrocyte membrane, lecithin: cholesteryl acyltransferase (LCAT) was also studied. It was found that the LCAT activity had a trend towards low values. However, crossing-over studies indicated that when the LCAT enzyme of patients was exposed to its own substrate it gave low activity values but that the result reverted to normal when control substrate was used.