One of those studies also observed impaired glucose tolerance and 60% reduced expression of KCNJ11 which encodes the Kir6.2 subunit of the potassium channel on the GLUT2 transporter (Gupta et al., 2005), although this was not replicated in another study where expression of Kir6.2 was normal (Pearson et al., 2007). This evidence concerns the gene KCNJ11 and Impaired glucose tolerance.