Increased risk of pneumonia associated with angiotensin-converting enzyme (CD143) rs4340 polymorphism

The study aims to investigate the genetic association between rs4340 polymorphism at intron 16 of the angiotensin-converting enzyme (CD143) gene and pneumonia predisposition. Electronic database of PubMed, Embase, and CNKI (China National Knowledge Infrastructure) was searched for the studies addressing the association between CD143 rs4340 genotypes and pneumonia risk. The odds ratio (OR) with its 95 % confidence interval (CI) was employed to estimate the association. In total, ten case–control studies, including 1239 pneumonia cases and 2400 healthy controls, met the inclusion criteria. Our results showed a significant association between rs4340 SNP and pneumonia risk using the recessive model (OR 1.43, 95 % CI 1.20–1.70). A significantly increased risk was also indicated under the recessive model in Asian populations (OR 1.63, 95 % CI 1.16–2.30), Caucasian populations (OR 1.34, 95 % CI 1.09–1.65), community-acquired pneumonia (OR 1.42, 95 % CI 1.16–1.75) rather than nosocomial pneumonia (OR 1.47, 95 % CI 0.97–2.23). However, further studies with gene–gene and gene–environmental interactions should be considered to confirm this association.