This review touches on three areas of recent research on genetic lipid disorders. The first is the advent of a trial of gene therapy for homozygous familial hypercholesterolemia. Affected individuals are at risk for myocardial infarction by adolescence. The experimental therapeutic protocol is aimed at restoring function of the defective low density lipoprotein (LDL) receptor gene in patients by introducing complementary DNA encoding normal LDL receptor into a patient's hepatocytes ex vivo. The second area reviewed concerns an important but lesser known relative of LDL, lipoprotein (a). Concentrations of lipoprotein (a) vary a thousandfold among humans. High levels pose a strong, independent risk for early heart disease, but lipoprotein (a) determinations are not yet routine. Finally, an update is presented on the controversy over cholesterol screening and treatment in childhood.