MYH11 and familial thoracic aortic aneurysm and aortic dissection: However, the expression of these genes in Myh11ΔK/ΔK aortas was not significantly lower than that in wild-type aortas (Supplementary Table S2), indicating that a predisposition to aortic dissection in mice harboring the Myh11 K1256 deletion mutation involves a pathway not previously recognized as associated with FTAAD.