Aim of the study: The aim of the study was to investigate possible associations of the Angiotensin – converting enzyme insertion/deletion (I/D ACE) polymorphism with gestational diabetes mellitus occurrence. Methods: Number of 53 healthy pregnant women (controls) and 48 women with gestational diabetes mellitus were included in the study. The woman patients were hospitalised in the Clinic of Obstetrics and Gynaecology, Masaryk University Affiliated hospital Brno during the period 10/2004 – 10/2005. In all cases there was the spontaneous one baby pregnancy. The procedure was obtaining the peripheral blood samples from women of those two groups and isolation of their DNA using standard technique with the use of proteinase K. I/D ACE genotype of each person was determined using allele specific primers. Results: We did not prove significant association neither of the genotype distribution (Pg) Pg = 0.115 nor allele frequency (Pa) Pa = 0.873 between controls and women with gestational diabetes mellitus. The significant differences of genotype distributions (Pg=0.03) were observed in women with two and more labours in anamnesis. Borderline significant differences of genotype distributions (Pg=0.08) were found in women with one and more abortions in anamnesis. Conclusions: According to our results the variability in ACE gene can be taken as factor contributing to manifestation of gestational diabetes mellitus. According to results of our study I/D ACE polymorphism can’t be taken as genetic marker of gestational diabetes mellitus.

        Key words: gestational diabetes mellitus, angiotensin-converting enzyme, gene polymorphism, renin-angiotensin system, pregnancy