Meta-analysis of the association between single nucleotide polymorphisms in TGF-β receptor genes and abdominal aortic aneurysm

Objective The role of transforming growth factor (TGF)-beta in abdominal aortic aneurysm (AAA) is controversial. The aim of this study was to assess the association of single nucleotide polymorphisms (SNPs) within TGFBR1 and TGFBR2 with AAA and infrarenal aortic diameter by combining data from previously published studies. Methods We performed a meta-analysis using individual subject data from three independent case-control groups from Western Australia (n = 1675), New Zealand (n = 1209), and the Netherlands (n = 1636) with 610, 601, and 693 cases of AAA (maximum infrarenal aortic diameter ≥30 mm), respectively. Data were available for two TGFBR1 (rs10819634, rs1571590) and six TGFBR2 (rs304839, rs1346907, rs1036095, rs9831477, rs9843143, rs764522) SNPs. Results There was marked heterogeneity between studies. The G alleles of the TGFBR2 rs764522 and rs1036095 SNPs were associated with AAA under a recessive model (OR = 1.69, 95% CI 1.28–2.25, P < 0.001 and OR = 1.59, 95% CI 1.23–2.07, P < 0.001) when a fixed effects model was used. Both associations remained significant after adjustment for multiple testing. Conclusion This study suggests that two common genetic polymorphisms in TGFBR2 are associated with the risk of developing AAA although this association was mainly driven by findings in the Netherlands group and marked between study heterogeneity was detected