This study was funded in 2014, with a focus on chimerism of cardiac myocytes (cardiac muscle cells) in a transplanted heart and how the organ recipient responds to the regenerative process after transplant. Chimerism refers to two or more different populations of genetically distinct cells existing within a single organism, which occurs during organ transplantation. 

This focuses on the different DNA between the patient and the transplanted organ. Initial damage is done to the heart originally by being taken from one body and put into another. You then have two different DNA confusing the immune system. This study is looking at the immune system interaction between donor and recipient DNA.