- Sensitivity of the Drosophila para sodium channel to DDT is not lowered by the super-kdr mutation M918T on the IIS4-S5 linker that profoundly reduces sensitivity to permethrin and deltamethrin. Usherwood, P.N., Vais, H., Khambay, B.P., Davies, T.G., Williamson, M.S. FEBS Lett. (2005)