Objective: Plasminogen activator inhibitor 1 is thought to play a role in the pathogenesis of obesity and insulin resistance. Therefore, we examined a single nucleotide exchange in this gene in women with gestational diabetes mellitus.
Methods: A total of 887 unselected women were prospectively screened for gestational diabetes mellitus by oral glucose testing between the 24th and 28th weeks of gestation. Eighty white women of this collective, 40 patients with a pathological oral glucose tolerance test and 40 normal control subjects, were randomly selected. DNA samples were isolated from the sera and analyzed for the functional -675 4G/5G promotor polymorphisms of the plasminogen activator inhibitor 1 gene.
Results: Women with gestational diabetes mellitus were significantly older and had a significantly higher body mass index (BMI) than those who did not have gestational diabetes mellitus. Women with normal glucose tolerance were significantly more often homozygous for the 5G allele (P = .01), independently of maternal age or BMI. Low fasting glucose values in the oral glucose tolerance test were significantly related to homozygosity for 5G (P = .02).
Conclusion: Homozygosity for the 5G allele of the plasminogen activator inhibitor 1 gene is associated with normal glucose tolerance in pregnant women. These findings further support a possible role of plasminogen activator inhibitor in the development of gestational diabetes mellitus.
Level of evidence: II-2.