NKX2-2 and Hyperglycemia: Importantly, Nkx2.2 mRNA levels and expression patterns in Nkx2.2SDmut/Cre embryos were similar to those of Nkx2.2Cre/+ animals at E18.5 (Fig. 1C,D), suggesting that the neonatal hyperglycemia in Nkx2.2SDmut/Cre mice did not arise from a loss of NKX2.2 expression during development.