Abnormal fatty acid composition of erythrocyte glycosphingolipids in congenital dyserythropoietic anemia type II.

Glycosphingolipids were isolated from the erythrocytes of three siblings clinically affected with congenital dyserythropoietic anemia type II (CDA-II) as well as from the erythrocytes of their parents and of normal individuals. Glycolipids were analyzed by thin-layer chromatography of their native and O-acetylated form and by high performance liquid chromatography of their O-acetyl-N-p-nitrobenzoyl derivatives. The glycolipid content of the CDA-II erythrocytes was 2.5 to 3 times higher than normal. This abnormal concentration resulted from a moderate accumulation of all the glycolipids present in normal erythrocytes and from a strong increase (at least 10 times over normal level) of lactotriaosyl- and lactoneotetraosylceramide. Glycolipids contained higher amounts of long chain fatty acids (C22-C24) in CDA-II patients than in controls. Free ceramide content of CDA-II erythrocytes was two times greater than the control value and the fatty acid composition was also altered.