Apolipoprotein polymorphism in Hungary.

The disorders of plasma apolipoprotein metabolism caused by a number of genetic and environmental factors are associated with atherosclerosis. Because of the distinct structural, epidemiological and genetic properties of apolipoproteins we have analyzed some potentially important phenotypical markers of apolipoproteins(a)/Lp(a)/,E (apo E) and A-IV (apo-A-IV). In our Hungarian study population (n = 202) the frequency of Lp(a) concentrations (mean 10.5 +/- 13.5 mg/dl) and phenotypes (the dominance of high molecular weight isoforms) show similar distribution that of other Caucasian populations. We have also found an inverse relationship between the concentrations and phenotypes of Lp(a). In accordance with earlier observation apo E polymorphism exerts a definitive effect on determinating variation of plasma cholesterol in our population. The average excesses of apo E alleles on serum cholesterol concentration were: E2 -0.34, E3 -0.01 and E4 +0.26 mmol/l. The apo E3 (0.807) allele was the most frequent followed by E4 (0.129) and E2 (0.064). In contrast, the apolipoprotein A-IV frequency distribution is significantly different from other Caucasian populations (p < 0.05). The frequency of apo A-IV alleles are f(A-IV1) = 0.95, f(A-IV2) = 0.039 and f(A-IV3) = 0.002. The association of apo A-IV phenotypes with HDL-cholesterol concentrations, which was previously described for two other European populations was only of borderline significance (p < 0.08). In conclusion, the results show the impact of phenotypic variation of apolipoproteins on the normal variation in the plasma lipid profile in Hungarian blood donors.