Validating Cardiac MRI Biomarkers and Genotype-Phenotype Correlations for DMD

This study will collect MRI from healthy volunteer boys and boys with Duchenne Muscular Dystrophy (DMD) to help researchers identify and validate cardiac MRI biomarkers to better understand the health of the heart and changes in heart health over time in boys with DMD. Currently, there is a lack of sufficiently well characterized cardiac MRI biomarkers that can serve as endpoints for detecting on-target and/or off-target cardiac effects during clinical drug trials for boys with DMD. Consequently, the first objective is to identify and characterize several cardiac MRI biomarkers for boys with DMD.

The second objective is to use their well-characterized cardiac MRI biomarkers and define their sensitivity for detecting early cardiac involvement. The final objective is to use these validated cardiac MRI biomarkers to better understand the genotype-phenotype correlation in boys with DMD, which to date remain tenuous. The investigators propose a pilot study to explore cardiac genotype-phenotype correlations in boys with DMD and outlier phenotypes using approaches they have pioneered for skeletal muscle.