To test this, we examined the nine candidates in the heterozygous background for tinman/NKX2-5, which in humans is well-known to contribute to a variety of CHD/HLHS manifestations (Elliott et al., 2003; Hrstka et al., 2017; Benson, 2010; Kobayashi et al., 2014). This evidence concerns the gene NKX2-5 and hypoplastic left heart syndrome.