 This 4 arm study will investigate the pharmacodynamics and pharmacokinetics of RO4998452 in type 2 diabetes patients with varying degrees of renal impairment. Eligible patients will be divided into 4 groups, with normal renal function, or mild, moderate or severe renal impairment. All patients will receive a single oral dose of RO4998452 in the fasted state.The anticipated time on study treatment is 3 months single dose studyand the target sample size is 100 individuals. 