Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 0 0 2026 05 19 1 7 Yabin Chen Department of Pediatrics, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China Hua Xu Department of Pediatrics, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China Xunchao Ji Department of Pediatrics, The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, China Juan Xiao Nursing and Rehabilitation College, Fuzhou Medical College, Fuzhou, Jiangxi, China 2025 12 08 2026 02 01 To investigate the association between single nucleotide polymorphism (SNP) of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) +49A/G locus and the risk of asthma in children by meta-analysis. Six databases were searched for records on the association between CTLA-4 +49A/G locus polymorphism and pediatric asthma. The retrieval time was from the establishment of each database to July 2024. Stata 15.0 software was applied, with the pooled OR and 95% CI calculated. Five genetic models (G/A, GA+AA/AA, G/GA+AA, GG/AA, and GA/AA) were analyzed. Nine studies were included, covering 2133 Cases and 1572 controls. The combined results exhibited that the differences were all statistically significant under the allelic (OR, 0.53; 95% CI, 0.35-0.79), dominant (OR, 0.41; 95% CI, 0.24-0.71), recessive(OR, 0.60; 95% CI, 0.41-0.89), homozygous (OR, 0.38; 95% CI, 0.22-0.68) and heterozygous (OR, 0.52; 95% CI, 0.33-0.80) models. The meta-analysis indicates that CTLA-4 +49A/G SNP is related to susceptibility to pediatric asthma, and allele G and genotype GG+GA, GG, and GA correlated with a decreased risk of asthma. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/4692 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/4692/2346