TBC1D4 and type 2 diabetes mellitus: We selected FOXP1, which has the most differentially methylated sites (n = 30; Fig. 3a), TBC1D4 (Fig. 3b), which has been implicated in T2D22 but the function of which has not been studied in human islets, and two genes (RHOT1 and CABLES1) that also had sites whose methylation in blood associated with future T2D (Table 2, Figs. 2d and 3c, d).