BAG3 and cardiomyopathy: One of the top candidate genes for racing ability is BAG3 (BCL2-associated athanogene 3, ECA1:12.8 Mb); variants and/or deletions in this gene have been associated with myopathies, neuropathies and cardiomyopathies in various human subpopulations (Franaszczyk et al., 2014; Kostera-Pruszczyk et al., 2015), suggesting a potential involvement of this gene in skeletal muscle and heart function, essential phenotypes for individuals with increased racing ability.