What are the genetic changes related to arrhythmogenic right ventricular cardiomyopathy ?
ARVC can result from mutations in at least eight genes. Many of these genes are involved in the function of desmosomes, which are structures that attach heart muscle cells to one another. Desmosomes provide strength to the myocardium and play a role in signaling between neighboring cells.  Mutations in the genes responsible for ARVC often impair the normal function of desmosomes. Without normal desmosomes, cells of the myocardium detach from one another and die, particularly when the heart muscle is placed under stress (such as during vigorous exercise). These changes primarily affect the myocardium surrounding the right ventricle, one of the two lower chambers of the heart. The damaged myocardium is gradually replaced by fat and scar tissue. As this abnormal tissue builds up, the walls of the right ventricle become stretched out, preventing the heart from pumping blood effectively. These changes also disrupt the electrical signals that control the heartbeat, which can lead to arrhythmia.  Gene mutations have been found in 30 to 40 percent of people with ARVC. Mutations in a gene called PKP2 are most common. In people without an identified mutation, the cause of the disorder is unknown. Researchers are looking for additional genetic factors, particularly those involved in the function of desmosomes, that may play a role in causing ARVC.