For example, SM22-restricted ablation of Integrin-linked kinase caused aortic aneurysm associated with perinatal lethality between E18.5 and P1, with no defects in OFT septation or ventricular development.50 This suggests that SM22-specific knock out can affect AS remodelling independently of effects on the progenitor cell populations contributing to OFT and ventricular remodelling, most likely through an impact on SMC and their progenitors. This evidence concerns the gene ILK and aortic aneurysm.