Microsatellite loci of the cattle tick Boophilus microplus (Acari: Ixodidae).

This brief communication reports the identification of microsatellite loci in the economically important tick species Boophilus microplus. The data are potentially useful in distinguishing different strains of B. microplus. Eight polymorphic loci were isolated in larvae, male and female adults analysed individually from 12 field isolates and laboratory strains from Australia (n = 8), Brazil, Mexico, Papua New Guinea and Zimbabwe. Nucleotide sequencing of alleles at these microsatellite loci revealed that non-repeat bases interrupted dinucleotide and tetranucleotide repeats in some loci. Loci with non-repeat bases interrupting them were shorter compared with loci that were not interrupted. Thus the presence of non-repeat bases in a repeated sequence seems to constrain the evolution of additional repeats by slip-strand misparing at these loci.