GENETIC-POLYMORPHISM OF APOLIPOPROTEIN-A-IV IN 5 DIFFERENT REGIONS OFEUROPE - RELATIONS TO PLASMA-LIPOPROTEINS AND TO HISTORY OF MYOCARDIAL-INFARCTION - THE EARS STUDY

As a part of the EARS study we assessed the role of the common apo A-I V polymorphism in determining the hereditary predisposition to cardiov ascular disease. The study population consisted of 1261 controls and 6 29 cases (students whose father had MI before 55 years) from five diff erent European regions. The apo A-IV 1-1 phenotype accounted for 85% o f the individuals. One per cent of subjects were homozygous for the ap o A-IV2 allele. There was significant regional variation in the apo A- IV allele frequencies from North to South in Europe, with the lowest A -IV2 frequency in Finland. The distribution of the apo A-IV phenotypes was similar in cases and controls, as was the regional variation. The apo A-IV polymorphism did not affect HDL cholesterol. There was no co rrelation between apo A-IV alleles and the plasma concentration of apo A-IV. The plasma concentration of apo A-IV was lower in females than in males; furthermore, there was a significant difference in apo A-IV concentrations between oral contraceptive users and nonusers: users ha d the lowest values. As no strongly significant genetic difference cou ld be demonstrated between plasma lipid concentration in cases and con trols, and as the apo A-IV polymorphism did not significantly influenc e plasma lipid concentration, we conclude that the apo A-IV gene is no t a major determinant of the risk for MI and/or CHD.