Skin-scale genetic structure of Sarcoptes scabiei populations from individual hosts: empirical evidence from Iberian ibex-derived mites

Abstract

The objective of the present study was to examine the extent of genetic diversity among Sarcoptes scabiei individuals belonging to different skin subunits of the body from individual mangy hosts. showing the proportion of shared alleles between pairs of individual mites representing three skin subpopulations (head, back, and abdomen subunits), allowed the clustering of some mite samples up to their skin subunits. This genetic diversity of S. scabiei at skin-scale did not have the same pattern in all considered hosts: for the first Iberian ibex (Cp1), only mites from the head subunit were grouped together; in the second individual (Cp2), the clustering was detected only for mites from the abdomen subunit; and for the third one (Cp3), only mites from the back subunit were clustered together. Our results suggest that the local colonization dynamics of S. scabiei would have influenced the nonrandom distribution of this ectoparasite, after a single infestation. Another presumable explanation to this skinscale genetic structure could be the repeated infestations. To our knowledge, this is the first documentation of genetic structuring among S. scabiei at individual host skin-scale. Further studies are warranted to highlight determining factors of such trend, but the pattern underlined in the present study should be taken into account in diagnosis and monitoring protocols for studying the population genetic structure and life cycle of this neglected but important ectoparasite.

Morphobiometrical and molecular study of two populations of Demodex folliculorum from humans

“…The skin-scale genetic pattern has been observed previously in S. scabiei isolated from head, abdomen and back of Iberian ibexes suggesting a local colonization dynamics after a single infestation or as the result of repeated (Alasaad et al 2008). Nevertheless, this fact needs to be tested.…”

Is ITS-2 rDNA suitable marker for genetic characterization of Sarcoptes mites from different wild animals in different geographic areas?

“…Also, microsatellite markers were used by Alasaad et al (2008a) to describe a new phenomenon of genetic structuring among S. scabiei at individual host skinscale level. On the other hand, Zahler et al (1999) analysed 23 pooled samples of mite isolates (not single mites) from nine host species in four continents, using the second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA) as genetic marker, and concluded that Sarcoptes consists of a single, heterogeneous species.…”

Coexistence of two different genotypes of Sarcoptes scabiei derived from companion dogs and wild raccoon dogs in Gifu, Japan: The genetic evidence for transmission between domestic and wild canids

“…As described by Alasaad et al (2008), nine specific microsatellites (Sarms 33,34,(36)(37)(38)40,41,44,and 45) of Sarcoptes mites were amplified with multiplex PCR. One primer from each set was 5 labeled with 6-FAM, VIC, NED, or PET ® fluorescent dye tag (Applied Biosystems, Foster City, CA, USA).…”