The work was aimed to study blood lipid spectrum in 133 patients with cholelithiasis (CL) and 159 with gallbladder cholesterosis (GC) as well as apoE genotypes (based on restriction fragment polymorphism) in 49 and 36 respectively. Lipid composition was shown to significantly differ in the two conditions. LDL cholesterol was increased in GC and TG in CL. A rise in LDL cholesterol in both groups was apparent before the age of 30 yr (34.6 +/- 8.4 and 52.6 +/- 12.9% respectively), that in TG and VLDL after 40 yr. E3/3 genotype (norm) was identified in 75.5 +/- 6.2% of the patients with CL and in 83.4 +/- 6.2% in those with GC (p 0.5), e2 allele in 14.5 +/- 5.0 and 8.1 +/- 4.5% (p < 0.05). These data suggest that patients of both groups equally frequently suffered disturbances in metabolism of saturated (e2 allele) and polyunsaturated (e4 allele) fatty acids predisposing for hypercholesterolemia and hyperlipidemia. They explain why CL is frequently associated with cholesterosis and GC with the formation of caliculi. However, the absence of significant correlation between CL, GC and alleles e2, e4 suggests participation of other factors in pathogenesis of these diseases (LP(a), LDL heterogeneity).