MYOCD has been shown to be essential for maintaining adult heart function.[27] Mice in which MYOCD is postnatally knocked down develop dilated cardiomyopathy and fatal heart failure.[28] A genetic study of Dominican families found evidence that MYOCD was associated with left atrial size.[29] Recent GWAS studies have found SNPs in MYOCD associated with PR interval duration[30] and atrial fibrillation[31] in European populations. The gene discussed is MYOCD; the disease is atrial fibrillation.