The relationship of NOS3 G894 T (rs1799983) gene polymorphism in the risk of congenital heart disease: a meta-analysis and bioinformatics study.

Nitric Oxide Synthase 3 (NOS3) G894 T (rs1799983) is an important regulator of cardiac development. Its role in congenital heart disease (CHD) has been extensively studied in recent years, but the results are contradictory. The aim of the present study was to better elucidate the relationship between the NOS3 G894 T gene polymorphism and susceptibility of CHD and its specific subtypes. A comprehensive literature search was conducted across several databases, including PubMed, Embase, Web of Science, Cochrane Library, CNKI, VIP, and Wan Fang. Meta-analysis was carried out using RevMan 5.4 software, and the odds ratio (OR) with 95% confidence intervals (CI) was used as the effect measure. Additionally, bioinformatics analysis was employed to explore the impact of NOS3 gene mutations on tetralogy of Fallot (TOF), using publicly available microarray datasets to assess NOS3 gene expression. Nine studies were included, comprising 1931 CHD cases and 1910 controls. Meta-analysis showed that the NOS3 G894 T polymorphism was associated with an increased risk of CHD in three genetic models: allele model (T vs G, OR = 1.31, 95% CI [1.02, 1.68], P = 0.04), homozygous model (TT vs GG, OR = 1.60, 95% CI [1.13, 2.26], P = 0.007), and dominant model (GT + TT vs GG, OR = 1.44, 95% CI [1.02, 2.05], P = 0.04). Subgroup analyses revealed a strong association with atrial septal defect (ASD), conotruncal defects (CTD), and septal defects, with the most significant correlation found for ASD. The NOS3 G894 T polymorphism was associated with the risk of CHD in ethnic subgroup, increasing the risk of CHD in white race. Bioinformatics analysis did not find significant differences in NOS3 gene expression between individuals with TOF. The NOS3 G894 T (rs1799983) gene polymorphism is significantly associated with the risk of CHD, with notable variations in this association across different regions and ethnic groups. The T allele increases the risk of CHD by 31% compared to the G allele. Additionally, this polymorphism is linked to specific CHD subtypes, especially ASD.