Two-dimensional gel electrophoresis was used to compare the protein profiles of two geographically isolated populations of the tick Rhipicephalus appendiculatus Neumann (Acari: Ixodidae) in Kenya. Most of the protein spots were common to both populations, but a number were specific to each population. Since proteins are encoded by genes, the presence of population-specific proteins suggests that there may be genetic differences between the two populations. It is proposed that some of these population-specific proteins might be related to the differences in susceptibility of the ticks to Tlwileria pnrva infection.
