RESUMO
Objective To study genomic polymorphic DNA and genetic distance of 7 species of ticks.\ Methods\ Ticks used in this study were Dermacentor nuttalli, D.silvarum, Haemaphysalis qinghaiensis, H.formosensis, H.punctata, Amblyomma testudinarium, and Ixodes ovatus. DNA extracts of the 7 species of ticks were amplified by random amplified polymorphic DNA (RAPD) and PCR technique using 5 primers with different arbitrary single chain polynucleotide sequences. DNA fingerprint maps were analyzed and the genetic distance among 7 species of ticks were counted. \ Results \ The amplified products of the 7 species of ticks by RAPD all showed their specific DNA band. The average genetic distance among them was 0^71. Conclusion RAPD can differentiate the 7 species of ticks.