Angiotensin-converting enzyme insertion-deletion polymorphism in normotensive and pre-eclamptic pregnancies

Objective To investigate the hypothesis that pre-eclampsia is associated with a common insertion-deletion polymorphism in the angiotensin-converting enzyme gene. Design Seventy-two women with pre-eclampsia and 83 normotensive pregnant women participated in the study. Pre-eclampsia was defined as a blood pressure exceeding 140/90 mmHg in a previously normotensive woman, associated with proteinuria in excess of 300 mg/l in a 24 h collection. Samples for fetal genotyping were available from 66 pregnancies complicated by pre-eclampsia and 79 normotensive pregnancies. Methods Maternal and fetal samples were genotyped at the insertion-deletion (I-D) polymorphism in intron 16 of the angiotensin-converting enzyme gene by the polymerase chain reaction followed by agarose electrophoresis. Results Neither the I-D genotype distributions nor the allele frequencies differed significantly between pre-eclamptic and normotensive pregnancies in maternal or fetal samples (X 2 < 0.3, not significant). The odds ratio for pre-eclampsia in women with the DD genotype, compared with the ID and II genotype, was 1.09 (95% confidence interval 0.55-2.16). The odds ratio associated with the DD genotype in the fetus was 1.14 (0.56-2.32). Conclusion This study has found no evidence that the insertion-deletion polymorphism in the angiotensin-converting enzyme gene is associated with pre-eclampsia.