GAD2 and Pitt-Hopkins syndrome: Finally, we observed that Tcf4STOP/+::Neurod6-Cre mice used a similar amount of nest materials as their respective controls, while Tcf4STOP/+::Gad2-Cre mice used more nest materials than Tcf4STOP/+ mice, but significantly less material than controls (Figure 2E), demonstrating that embryonic reinstatement in glutamatergic neurons was sufficient to prevent the impaired nest building phenotype in PTHS model mice.