Frequency of mononuclear diploid cardiomyocytes underlies natural variation in heart regeneration

Henry Sucov and colleagues demonstrate substantial natural variation in the capacity of the mouse heart to regenerate after injury and link this to the prevalence of mononuclear diploid cardiomyocytes. They identify Tnni3k as one gene that contributes to the observed variation and validate its role through mouse knockout and zebrafish overexpression studies.