A DNA-FINGERPRINTING SYSTEM FOR THE ECTOPARASITE SARCOPTES-SCABIEI

We describe multiple hypervariable microsatellites that will provide a highly informative genetic marker system for the sarcoptid mite Sarco ptes scabiei. Eighteen positive clones containing the highly repetitiv e sequence (GA)(n) were isolated from a partial genomic library of S. scabiei. Ten of these clones were characterised by sequencing and prim ers were designed from the unique sequences flanking eight microsatell ite loci. Genomic DNA was subsequently extracted from individual mites and the repeat blocks were amplified by way of [gamma(33)P] ATp end-l abelled polymerase chain reaction. Fragment length polymorphisms were revealed in three of the loci when resolved on polyacrylamide sequenci ng gels. The high levels of allelic variability demonstrated between i ndividual mites enable these three loci to form a DNA fingerprinting s ystem that will be suitable for epidemiological and taxonomic studies both within and between host species. (C) 1997 Elsevier Science B.V.