The clinical and pathogenetic features of preeclampsia in the ACE I/D gene polymorphic variant and ADD1 G460W gene subgroups were studied in 168 patients with preeclampsia and 112 pregnant women with physiological pregnancy. The ACE I/D gene was associated with the occurrence of preeclampsia and the risk for this complication of pregnancy is much higher in the combination of ACE gene DD and ID genotypes and the GW genotype of the ADD1 G460W gene polymorphism, which in the dilocus combination were related to the highest values of average daily diastolic blood pressure. In both groups, the genotypes with the D allele in the ACE gene were associated with the enhanced activity of angiotensin-converting enzyme with its considerable increase in the level of this enzyme in hypertensive patients having the ACE gene DD genotype, as compared with the control group. In the preeclampsia group, the dilocus combination of the II-GW genotypes of ACE I/D and ADD1 G460W polymorphisms was associated with the lower concentration of aldosterone and the W allele of the polymorphic locus G460W of the ADD1 gene was related to diminished sodium excretion whereas the reduced activity of renin in patients with arterial hypertension was unassociated with the above gene polymorphic variants.