ABCB1 and Posterior Leukoencephalopathy Syndrome: ABCB1 rs1045642 TT was also in inverse association with seizure and PRES in the Combined cohort (p = 0.011, OR = 0.34, CI95% (0.15–0.78), p = 0.017, OR = 2.10, CI95% (1.14–3.87), respectively) (Figure 4).