AXIN1 and ventricular septal defect 1: Gonzales-Pena et al. recently reported a relationship between maternal dietary folic acid consumption and lower methylation status of Axis inhibitor 1 (AXIN1) gene and higher methylation status of T-box transcription factor 20 (TBX20) genes associated with a ventricular septal defect in children [71] Both genes have been previously shown to be related to CHD [72].