The goals of this study were to compare the allelic distribution of the apolipoprotein E(apoE) gene in Hungarian and Hungarian Gypsy children and to examine the impact of apoE polymorphism on quantitative levels of lipids in the two racial groups. Our data yielded calculated allele frequencies of 6.4% and 8.9% for apoE2; 83.8% and 73.8% for apoE3; and 9.8% and 17.3% for apoE4 in Hungarian and in Gypsy children, respectively. The frequency of the apoE4 allele was significantly higher (P<0.05) in Gypsy children than in Hungarians. The effect of apoE genotypes on serum lipid parameters differed considerably in the two racial groups. In the Gypsy group the lowest total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C) and triglyceride levels were in the E3/E3 group and these values differed significantly (P<0.0001 for TC and LDL-C and P<0.01 for triglyceride) from the values in the E2/E3 and E3/E4 groups. There were no significant differences in TC, LDL-C and triglyceride levels between E2/E3 and E3/E4 groups. The high-density lipoprotein-cholesterol (HDL-C) levels did not differ significantly among the genotype groups. In Hungarian children, the apoE2/3 group displayed lower, the E3/4 group higher, values of TC and LDL-C than in the E3/3 group, but the differences were not significant (P>0.05). HDL-C and triglyceride values did not differ among the genotype groups.
Conclusion: Our results demonstrate that the apolipoprotein E allele frequencies differ between Hungarian and Gypsy children and suggest that these alleles influence the serum lipid levels, but other genetic and environmental factors can considerably change this effect.