EP300 and familial atrioventricular septal defect: Alterations in the expression levels of the EP300 (histone acetyltransferase p300), KAT2A (lysine acetyltransferase 2A), and HAT1 (human histone acetyltransferase 1) acetylases also seem to play a role in the onset of CHDs with ASDs (atrial septal defects), VSDs, AVSDs (atrioventricular septal defects), and valve dysplasia [73,74].