RESUMEN
@#Scabies occurs in human due to the burrowing ectoparasite Sarcoptes scabiei var. hominis resulting in intense itching and inflammation, and manifesting as a skin allergy. Limited information is available about the genetic diversity of S. scabiei in human. In this study, we characterized S. scabiei var. hominis using nuclear marker ITS-2, mitochondrial marker 16S and microsatellite markers. To examine the extent of the genetic variation, individual mite gDNA was first amplified using ITS-2, 16S and microsatellite primers by PCR, later amplicons were sequenced directly and analysed by MEGA 7. Sequence analysis of ITS- 2 showed no host segregation and geographical isolation, whereas 16S indicated presence of both hosts adapted and geographically segregated populations of S. scabiei. Results of microsatellites revealed polymorphism as allelic variability between and within the populations studied. The different varieties of Sarcoptes mites belong to different host species and geographic regions recommended that Sarcoptes mites are genetically isolated. This is the first report on the molecular characterization of S. scabiei var. hominis from Pakistan. Additionally, genetic studies including a greater number of specimens are required to comprehend the molecular epidemiology of Sarcoptes mite in Pakistan.
RESUMEN
Infestation of the skin by the "itch mite" Sarcoptes scabiei var. hominis results in a contagious skin infection in humans called "scabies". By resolving morphology issues, the present study was designed to be acquainted with itch mite by molecular markers. The mite samples were collected from scabies patients by visiting government hospitals of twin City, Pakistan. For successful mo-lecular detection approach, preparation of Sarcoptes mite DNA by commercial DNA extraction kit method. Furthermore, two primers i.e. Sarms 15 F/R and 16S D1/D2 were used to amplify target sequence by using PCR. The amplified products were then separated by agarose gel, electrophoresis and analyzed after staining and visualizing in UV transilluminator. Analysis of PCR product showed one specific band of 178 bp with primer Sarms 15 F/R, while, with primer 16S D1/D2 bands of 460 bp and 600 bp were observed on 2% agarose gel. The appearance of different band of 600 bp revealed that it might be due to heteroplasmy state present in the Pakistani Sarcoptes mites population. Current study adds validity to the claim that PCR is more accurate, specific and sensitive in the detection of the ectoparasites even in smallest amount