Cumulative evidence of the genetic association between SP-B C1580T polymorphisms and risk of neonatal respiratory distress syndrome.

Surfactant protein SP-B, an important protein in pulmonary surfactant, is required for the stabilization of surfactant films in the lung and maintenance of postnatal lung function. Although the association between SP-B polymorphisms and the risk of neonatal respiratory distress syndrome (RDS) has been evaluated, the results have been inconsistent. We investigated the association between SP-B polymorphisms and the risk of neonatal RDS. Relevant studies were systematically searched in PubMed, EMBASE, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) electronic databases until June 2022. Data were collected independently by two reviewers and converted to odds ratios (ORs) with 95% confidence intervals (CIs). Meta-analysis, subgroup analysis, sensitivity analysis, and publication bias assessment were performed using Stata 12.1 software and Review Manager 5.3. Fourteen studies were included. C1580T polymorphism was significantly associated with neonatal RDS in five genetic models (T vs. C: OR = 0.70, 95% CI 0.57-0.86, I = 78%; TT vs. CC: OR = 0.63, 95% CI 0.53-0.86, I = 39%; CT vs. CC: OR = 0.65, 95% CI 0.50-0.84, I = 54%; TT + CT vs. CC: OR = 0.62, 95% CI 0.49-0.78, I = 59%; TT vs. CC + CT: OR = 0.78, 95% CI 0.67-0.91, I = 43%). The CT and TT genotypes may decrease the risk of RDS in neonates. Subgroup analyses revealed that the association of C1580T polymorphism with neonatal RDS was stable, independent of preterm birth and Hardy-Weinberg equilibrium. In addition, the Han Chinese were more likely to be affected by C1580T polymorphisms than Caucasians and Finnish. Our findings suggest that C1580T polymorphism may be a protective factor against neonatal RDS.