Extracellular superoxide dismutase (SOD3) ALA40THR genetic polymorphism in correlation to Doppler flow indices in the Egyptian preeclamptic patients

Abstract

<br><b>Background</b><br>Preeclampsia (PE) is a common pregnancy-specific complication, characterized by hypertension and significant proteinuria at or after 20 weeks of pregnancy; it affects ∼ 5–10% of pregnant women worldwide and remains the second leading cause of maternal and perinatal morbidity and mortality. Depletion of antioxidant enzymes such as superoxide dismutase (SOD) might be associated with the development of PE.<br><b>Objective</b><br>This study aimed to investigate the correlation of Ala40Thr polymorphism of SOD3 gene with the severity of PE and its correlation to fetal Doppler flow indices.<br><b>Materials and methods</b><br>The study was conducted in 250 pregnant women, divided into three groups: 130 controls, 60 mild PE cases, and 60 severe PE cases. They all underwent transabdominal ultrasound for assessment of resistance index and pulsatility index. The polymorphism was detected by PCR restriction fragment length polymorphism.<br><b>Results</b><br>There was a significant difference in the SOD3 Ala40Thr polymorphism between preeclamptic patients and controls, with higher risk of mutant GG variant compared with the wild-type AA in patients. The gestational age at delivery and pulsatility index were found to be significantly different among the three genotypes, with higher pulsatility index in severe cases compared with mild cases.<br><b>Conclusion</b><br>Follow-up of resistance index and pulsatility index with genotyping of SOD3 can give a clue for early prediction of PE avoiding preterm labor and intrauterine growth restriction.<br>