IDO1 and Stroke: Moreover, we found that the G/G-T/T, G/G-C/C and G/C-C/C genotypes of c.-1493G>C – IDO1 (rs10089084) and c.975-7T > C– KAT2 (rs1480544) increased the risk of stroke about four times (p = 0.009), 18 times (p < 0.001) and three times (p < 0.001), respectively.