MYH6-Cre Insertion Accelerates Cardiac Phenotype in Dystrophic D2-mdx Mice

Abstract

Duchenne Muscular Dystrophy (DMD) is a progressive muscular degenerative disease that is recessively inherited through the X chromosome. Various mutations in the dystrophin gene lead to noticeable muscle weakness. The effects on skeletal and cardiac tissue result in progressive immobility and cardiac dysfunction, respectively. There are several murine models used to study DMD; however, there are still limitations in replicating the pathology of the disease seen in humans with DMD. Myh6cre(Cre) genotypic modification through the Cre/LoxP system has been proposed to further develop the pathology in murine models to specifically target cardiac tissue while allowing further alteration downstream in the mouse's lifespan. Initial observation of obesity in conjunction with premature death compared to traditional dystrophin-affected mice prompted us to take a further look into fibrosis and cardiac dysfunction. Our findings may help define the phenotype of dystrophin knockout, Cre-positive mice and display the potential for a more accurate, pathological model for DMD.