Conversely, although increased expression of Ago2 causes transient glucose intolerance in dox-Ago2 mice, these mice have normal circulating glucose and insulin levels and insulin sensitivity, and therefore it is unlikely that the increase in Ago2 levels in the islets of ob/ob mice plays a causal role in the hyperglycemia or hyperinsulinemia. This evidence concerns the gene AGO2 and hyperinsulinism.