Genetic basis and impact of tick acaricide resistance.

Acaricide resistance in Boophilus microplus has been studied for the last 20 years from the toxicology, metabolic and genomic points of view, however, only few methods for molecular detection of resistance have been developed. Despite the relatively poor sensitivity for resistance detection, bioassays remain the method of choice for susceptibility evaluation of tick populations, based on their toxicological response after exposure to acaricides. Metabolic detoxification of acaricides is known to be mediated by multigene- families of enzymes such as GST, Esterases and Mixed Function Oxidases (cytochrome P450). In addition, target site insensitivity has been studied on the sodium channel and acetylcholinesterase genes. The use of genomics to understand acaricide resistance in B. microplus will play a major role in unraveling the molecular mechanisms of resistance. Advances in genomics, will accelerate the development of new diagnostic and immunoprophylactic tools based on new vaccine candidates, and new molecular targets for acaricide resistance detection and improvement of strategies for the control of ticks and tick-borne diseases in tropical and subtropical areas of Mexico.