The association between collagen gene polymorphisms and intracranial aneurysms: a meta-analysis

The association between single nucleotide polymorphisms (SNPs) of the collagen gene and intracranial aneurysm (IA) pathogenesis remains controversial. Thus, in this study, a meta-analysis was performed to evaluate the association between collagen gene SNPs and the incidence of IA. A systematic search of major online databases up to March 2017 was performed. Five genetic models (allelic, dominant, recessive, heterozygous, and homozygous models) were used to analyze the associations. A total of 14 trials with 13,709 patients were included. Four collagen genes, COL1A2 (21 SNPs), COL3A1 (7 SNPs), COL4A1 (6 SNPs), and COL4A2 (1 SNP), were analyzed. We observed that rs42524 in the COL1A2 gene was associated with a significant increase in the risk of IA in Japanese patients (allelic model: OR, 1.94; 95% CI, 1.03–3.64; p = 0.04); the rs1800255 polymorphism in the COL3A1 gene was significantly correlated with Chinese IA patients (allelic model: OR, 1.50; 95% CI, 1.30–1.73; p < 0.001); and rs2621215 was significantly correlated with IA for the heterozygous model (OR, 1.58; 95% CI, 1.15–2.17; p = 0.005) and the dominant model (OR, 1.49; 95% CI, 1.09–2.02; p = 0.012). Furthermore, in the COL4A1 gene, there was a significant relationship between the rs3783107 polymorphism and a Dutch IA population (allelic model: OR, 1.23; 95% CI, 1.06–1.42; p = 0.006), and the prevalence ratio of mutation carriers in the Dutch population was significantly higher than that in the Japanese population (ROR, 1.31; 95% CI, 1.07–1.63; p = 0.008). The rs1800255 polymorphism in COL3A1 is robustly correlated with IA in the Chinese population. Three COL1A2 SNPs—rs42524, rs1800238, and rs2621215—should be studied further.