ABCB1 and Parkinson disease: The combined data showed that ABCB1 3435C/T polymorphism was not associated with the susceptibility to PD in 5 genetic models (allelic T vs C: OR = 1.01, 95%CI 0.94–1.10, P = 0.73; heterozygous TC vs CC: OR = 0.95, 95%CI 0.83–1.09, P = 0.45; homozygous TT vs CC: OR = 1.04, 95%CI 0.89–1.22, P = 0.64; recessive TT vs TC + CC: OR = 1.07, 95%CI 0.94–1.22, P = 0.31; and dominant TT+TC vs CC: OR = 0.97, 95%CI 0.86–1.10, P = 0.91) (Table 3).