The blind cavefish: Unravelling the mechanisms underlying heart regeneration

Whereas the human heart has no inherent ability to regenerate cardiac muscle after myocardial infarction, certain fish efficiently repair their hearts. Astyanax mexicanus, a close relative of the zebrafish, is a single fish species comprising cave-dwelling and surface river populations. Remarkably, while surface fish regenerate their heart after injury, cavefish cannot and form a permanent fibrotic scar, similar to humans. The difference in heart regeneration capacity within one species makes Astyanax mexicanus a unique and powerful model to link the ability for heart regeneration directly to the genome using Quantitative Trait Loci analysis. This allows us to study the most fundamental molecular mechanisms that are prerequisite to creating a cellular environment favouring heart regeneration over scarring. Preliminary results indicate that we will be able link the ability for heart regeneration directly to a small number of loci containing a limited number of genes.