KDM6A and Neurodevelopmental delay: Our cohort included 21 with LOF DNMs and 12 phase-unknown LOFs in KMT2D (SI Appendix, Table S19) and one LOF in KDM6A. CHD phenotypes were HLHS, CTD, and LVO, and all but two probands had EC, NDD, or both (SI Appendix, Table S19).