Maternal and offspring methylenetetrahydrofolate reductase gene C677T polymorphism: does it influence the prevalence of congenital heart defects in Egyptian neonates?

Congenital heart defects (CHDs) are the most prevalent heart diseases in neonates. There is evidence suggesting that the risk of CHDs may be related to the folate status as well as the genetic variants in folate-related genes. Investigating the relationship between methyltetrahydrofolate reductase (MTHFR) C677T gene polymorphism and CHDs in full-term neonates and considering the possible protective role of folate supplementation were made. This study included 26 cases, 18 controls, and their biological mothers. Echocardiography was performed to all neonates for diagnosis of the type of congenital heart disease. Mothers and their off springs were subjected to DNA analysis for MTHFR C677T using polymerase chain reaction restricted fragment length polymorphism. An association between maternal (p = 0.044) and infant (p = 0.001) MTHFR C677T polymorphism and transposition of great vessels (d-TGA) was found. Odds ratio (OR) for the genotypes CT and TT versus CC was 10, with 95 % confidence limits (CI) (1.05–95.23) and OR 26 with 95 % CI (2.60–259.29), respectively. Also for the genotypes CT and TT versus CC, an association was found between infant MTHFR C677T polymorphism and atrial septal defect [p = 0.000; OR 36.4; 95 % CI (3.7–354.40)], ventricular septal defect [p = 0.025; OR 5.2; 95 % CI (1.2–23.04)], as well as patent ductus arteriosus [p = 0.000; OR 33.8; 95 % CI (3.5–330.62)]. Maternal folic acid supplementation proved protective against CHDs. MTHFR C677T polymorphism is associated with certain subgroups of CHDs.