Background: A significant cause of maternal and perinatal morbidity and mortality is
preeclampsia, a pregnancy complication that has recently been responsible for 10 to 15%
of fatalities among pregnant women globally. Purpose: to clarify the role of microRNA
155 and endothelial Nitric Oxide Synthase (eNOS) gene variants as diagnostic and
predictive biomarkers in patients with preeclampsia. Patients and Methods: This case
control study was conducted at the Departments of Gynecology & Obstetrics and Medical
Biochemistry & Molecular Biology, Faculty of Medicine, Benha University, during the
period from January 2024 to January 2025. The study was carried out on 100 pregnant
women who were categorized into 3 groups: control group: included 30 normotensive
pregnant women, gestational hypertension group: 30 pregnant women with gestational
hypertension and preeclampsia group: 40 pregnant women who were clinically diagnosed
with preeclampsia. MicroRNA-155 expression and the frequency of eNOS gene variants
were measured in all groups. Results: In comparison to the control group, the expression
level of microRNA-155 was markedly increased in both the gestational hypertension and
preeclampsia groups. Median expression values increased progressively across the groups:
0.99 in controls, 1.40 in gestational hypertension, and 7.0 in preeclampsia. Regarding
eNOS gene polymorphism (G894T), the frequency of the T allele was higher in the
preeclampsia group (31.25%) as compared to gestational hypertension (26.7%) and
controls (21.7%). Conclusions: microRNA-155 may be a promising diagnostic and
predictive biomarker for preeclampsia. Preeclampsia is more common in people who carry
the eNOS 894T allele.