Erythrocyte membrane alterations in lecithin:cholesterol acyltransferase deficiency.

Structural, compositional, and functional abnormalities were found in the erythrocyte membranes of homozygotes for LCAT deficiency. Similar but less pronounced abnormalities were also present in the heterozygotes for this disorder. Some of the membrane alterations, which included decreased osmotic fragility, changes in phospholipid composition, and membrane sulfydryl group latency, as well as changes in the activity of membrane p-nitrophenylphosphatases and acetylcholinesterase, may be secondary to the changes in plasma lipids. However, since plasma lipids (and LCAT activity) were normal in the hereozygotes, the existence in both the homo- and the heterozygotes of erythrocyte membrane abnormalities unrelated to plasma LCAT activity seems likely.