High-density lipoprotein (HDL), HDL2, and HDL3 cholesterol concentrations determined in serum of newborns, infants, children, adolescents, and adults by use of a micromethod for combined precipitation ultracentrifugation.

Cholesterol (C) concentrations in the two major subfractions of high-density lipoproteins (HDL2-C and HDL3-C) in sera from both sexes, ages ranging from newborns to adults, were measured by use of a micromethod for combined precipitation-ultracentrifugation. Sera were obtained from 91 boys, 68 girls, 15 healthy men, and 14 women. The HDL2-C concentration was higher in women than in men; the HDL3-C concentration was similar in these two groups. This sex-related difference, generally seen in adults, was found to begin at ages 11-15 y. The value of HDL2-C in females increased with age in a stepwise manner, whereas that in males increased up to ages 6-10 y but tended to decline thereafter. The HDL3-C concentration was higher in the adults than in the children. This micromethod for separating operationally defined HDL subfractions is of value for lipoprotein research in children.