[Detection of a new lipoprotein: Lp(a). Its occurrence in atherosclerosis with or without hyperlipemia].

Detected using a method involving gradient electrophoresis on polyacrylamide gel, the presence of a high level of an Lp(a) was demonstrated in 17% of control subjects and 39% oh hyperlipidaemic subjects explored. The difference appeared to be particularly significant in subjects with a pure hypercholesterolaemia (type IIA) or dominant hypercholesterolaemia (type IIB), which may be accounted for by the antigenic communities and related substances in the lipid composition uniting Lp(a) to LDL. The association of frank atherosclerosis with the hyperlipidaemia substantially increased the frequency of high levels of circulating Lp(a). A combined elevation of levels of Lp(a) and LDL would seem to be associated with a particular atherogenic power.