APOPROTEIN E PHENOTYPE DETERMINES SERUM-CHOLESTEROL IN INFANTS DURINGBOTH HIGH-CHOLESTEROL BREAST-FEEDING AND LOW-CHOLESTEROL FORMULA FEEDING

Our objective was to establish the role of the apoprotein (ape) E phen otype in determining serum cholesterol levels in infants fed exclusive ly on high-fat, high-cholesterol human milk and in those fed a low-cho lesterol, high-unsaturated fat formula. The total and lipoprotein chol esterol, apoB, and triglyceride concentrations in serum were quantifie d and related to the apoE phenotype in 151 infants at birth and at 2, 6, 9, and 12 months of age. Forty-four had the E3/4 or 4/4 phenotype ( E4 group), 94 had the E3/3 phenotype (E3 group), and 13 had the E2/3 o r 2/4 phenotype (E2 group). In cord blood, cholesterol concentrations tended to be higher in the E4 than in the E2 group. With exclusive bre ast-feeding, the concentrations rose significantly faster and higher i n the E4 group than in the E3 group or, especially, the E2 group. The values (mmol/L, mean +/- SEM) were 1.6 +/- 0.15, 1.5 +/- 0.05, 1.4 +/- 0.1 (P = n.s.) at birth; 4.2 +/- 0.1, 3.8 +/- 0.08, 3.4 +/- 0.2 (P < 0.001) at 2 months; 4.4 +/- 0.15, 3.9 +/- 0.1, 3.4 +/- 0.15 (P < 0.001 ) at 4 months; 4.3 +/- 0.17, 4.0 +/- 0.13, 3.7 +/- 0.26 (P < 0.001) at 6 months; 4.8 +/- 0.28, 4.4 +/- 0.11, 3.8 +/- 0.05 (P < 0.001) at 9 m onths; and 4.1 +/- 0.11, 4.4 +/- 0.08, 4.1 +/- 0.19 (P < 0.001) at 12 months, for the E4, E3, and E2 groups, respectively. Increases in LDL cholesterol and LDL apoB behaved similarly. The total triglyceride, an d total HDL, HDL2, and HDL3 cholesterol concentrations did not depend on the apoE phenotype. Among infants fed high-fat, high-cholesterol hu man milk, the total and LDL-cholesterol concentrations and the LDL apo B concentration of those with the apoE phenotype 4/4 or 3/4 rose faste r and to higher levels than in other infants. Among formula-fed infant s, receiving a low-cholesterol, high-unsaturated fat diet, the differe nces between the apoE groups were smaller.