We have analyzed allele frequency distribution at the hypervariable locus 3' to the apolipoprotein B gene in a healthy population sample (241 women and 246 men) from the Belgrade area. The bimodal distribution of sixteen different hypervariable region (HVR) alleles and the heterozygosity index (average 0.76) in both samples are similar to ones reported for other Caucasian populations. However, we found the hypervariable element containing 34 repeats-HVE34 allele to be the most common one in both female and male samples, and that there was a lower frequency of the HVE>36 alleles. For further analysis of 3'HVR allele frequency and its possible association with serum lipid levels, all HVR alleles were grouped into five main types (HVE<32, HVE32, HVE34, HVE36, and HVE>36), and the samples were divided into lipid quartiles. We found that (1) apo B gene 3'HVR polymorphism is associated with variation of normal lipid levels in males, (2) HVE32 alleles are associated with decreased serum levels of total cholesterol, LDL cholesterol, and triglycerides, and (3) HVR genotypes containing HVE34 and HVE36 alleles are associated with elevated serum levels of total cholesterol, low density lipoprotein (LDL) cholesterol, and triglycerides.