TGFB1 and pulmonary emphysema: The TGFB1 rs2241718 and MMP9 rs3918242 SNPs were associated with centrilobular emphysema (p = 0.022 and p = 0.008, respectively), and the TNF rs1800629 SNP was associated with paraseptal emphysema (p = 0.017) (Table 3).