Validation of PCR Assay for Identification of Sarcoptes scabiei var. hominis.
AbstractBackground: Infestation of the skin by the “itch mite” Sarcoptes scabiei var. hominis results in a contagious skin infection in humans called “sca-bies”. By resolving morphology issues, the present study was designed to be acquainted with itch mite by molecular markers. Methods: 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 com-mercial 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. Results: 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. Conclusion: 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.
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