TCF4 and Pitt-Hopkins syndrome: For instance, TCF4 haploinsufficiencyis known to result in clinical manifestations of PTHS in patients, whereas heterozygous mice carryingTcf4 mutations (wt/Tcf4–) tend to exhibit milder phenotypes(Thaxton et al., 2018; Li H. et al., 2019; Mesman et al., 2020;Wang et al., 2020).