Syndromes associated with HLHS include Turner syndrome (loss of part or all of an X chromosome in females), 22q11.2 deletion syndrome, Jacobsen Syndrome (11q terminal deletion disorder), Kabuki syndrome (single gene variants in KMT2D and KDM6A), VACTERL association (genetic origin unknown), Rubinstein-Taybi (single gene variants in CBP and EP300), Adams-Oliver syndrome (single gene variants in ARHGAP31, DOCK6, RBPJ, EOGT, NOTCH1, DLL4), and Beckwith-Wiedemann syndrome (single gene variants in CDKNIC) (25). The gene discussed is KDM6A; the disease is hypoplastic left heart syndrome.