We find that basal (fasting) serum insulin values are similar between genotypes (Fig. 8g), however, with glucose stimulation insulin secretion is significantly impaired in Tm-induced Ins1CreERT2;Swell1fl/fl (+) mice compared to Tm-induced Swell1fl/fl mice (+) (Fig. 8g, h), and this is also associated with impaired glucose tolerance (Fig. 8i). This evidence concerns the gene INS and Impaired glucose tolerance.