Abstract
Patient with familial high density lipoprotein deficiency, Tangier disease, found in Miyazaki had an abnormal electrophoretic mobility of serum LDL which moved faster than that of normal LDL on polyacrylamide gel electrophoresis. In consistent with this finding, gel filtration using high performance liquid chromatography showed the decrease in size of LDL particles in the patient's serum; relative elution volume of LDL to serum albumin were (mean±SD) 0.886±0.008 for homozygotes and 0.851±0.005 for normal subjects. Abnormality present in LDL was also observed in fatty acid composition of cholestryl ester. In these patients, saturated fatty acid compositions (mean±SD, %) were increased to 5.56±1.09 (2.85±0.63) in C-14, 28.17±2.10 (19.38±1.79) in C-16 and 15.19±1.04 (7.89±2.23) in C-18, compared with those obtained from normal subjects as shown in parentheses, while unsaturated fatty acid compositions were decreased to 11.83±2.07 (17.04±1.66) in C-18: 1 and 32.90±2.55 (47.69±3.93) in C-18: 2 except for the value observed in C-16: 1. On the other hand, no abnormality was observed in fatty acid composition of total serum cholesteryl ester. These results together with the normal ester ratio in cholesterol suggested that the cholesterol esterifying mechanism proceeded normally but metabolism of lipoprotein particles containing cholesteryl ester of normal fatty acid composition was disturbed in Tangier disease.
Another abnormality was found in serum HDL of heterozygotes in Tangier disease. Gel filtration showed that HDL2, normally a main component of HDL, was decreased as well as the results on the gel electrophoresis. This fact suggested the disturbance of interchange of HDL2 and HDL3.
