Comparison of six commercially available STR kits for their application to touch DNA using direct PCR

Analytical techniques such as DNA profiling are widely used in various fields, including forensic science, and novel technologies such as direct polymerase chain reaction (PCR) amplification are continuously being developed in order to acquire DNA profiles efficiently. However, non-specific amplification may occur depending on the quality of the crime scene evidence and amplification methods employed. In particular, the ski-slope effect observed in direct PCR amplification has led to inaccurate interpretations of the DNA profile results. In this study, we aimed to reduce the ski-slope effect by using dimethyl sulfoxide (DMSO) in direct PCR. We confirmed that DMSO (3.75%, v/v) increased the amplification yield of large-sized DNA sequences more than that of small-sized ones. Using 50 Korean buccal samples, we further demonstrated that DMSO reduced the ski-slope effect in direct PCR. These results suggest that the experimental method developed in this study is suitable for direct PCR and may help to successfully obtain DNA profiles from various types of evidence at crime scenes.

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Back to Amido Black : Uncovering touch DNA in blood‐contaminated fingermarks

Journal of Forensic Sciences ◽

10.1111/1556-4029.14783 ◽

2021 ◽

Author(s):

Yinon Harush‐Brosh ◽

Yael Levy‐Herman ◽

Ravell Bengiat ◽

Carla Oz ◽

Michal Levin‐Elad ◽

...

Keyword(s):

Touch Dna ◽

Amido Black

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Development of a Co-Dominant Cleaved Amplified Polymorphic Sequences Assay for the Rapid Detection and Differentiation of Two Pathogenic Clarireedia spp. Associated with Dollar Spot in Turfgrass

Agronomy ◽

10.3390/agronomy11081489 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1489

Author(s):

Tammy Stackhouse ◽

Sumyya Waliullah ◽

Alfredo D. Martinez-Espinoza ◽

Bochra Bahri ◽

Emran Ali

Keyword(s):

Pcr Primers ◽

The United States ◽

Fungal Species ◽

Dollar Spot ◽

Direct Pcr ◽

Specific Pcr ◽

Specificity And Sensitivity ◽

Pure Cultures ◽

Speed Up ◽

Cleaved Amplified Polymorphic Sequences

Dollar spot is one of the most destructive diseases in turfgrass. The causal agents belong to the genus Clarireedia, which are known for causing necrotic, sunken spots in turfgrass that coalesce into large damaged areas. In low tolerance settings like turfgrass, it is of vital importance to rapidly detect and identify the pathogens. There are a few methods available to identify the genus Clarireedia, but none of those are rapid enough and characterize down to the species level. This study produced a co-dominant cleaved amplified polymorphic sequences (CAPS) test that differentiates between C. jacksonii and C. monteithiana, the two species that cause dollar spot disease within the United States. The calmodulin gene (CaM) was targeted to generate Clarireedia spp. specific PCR primers. The CAPS assay was optimized and tested for specificity and sensitivity using DNA extracted from pure cultures of two Clarireedia spp. and other closely related fungal species. The results showed that the newly developed primer set could amplify both species and was highly sensitive as it detected DNA concentrations as low as 0.005 ng/µL. The assay was further validated using direct PCR to speed up the diagnosis process. This drastically reduces the time needed to identify the dollar spot pathogens. The resulting assay could be used throughout turfgrass settings for a rapid and precise identification method in the US.

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Timely gene detection assay and reliable screening of genetically engineered plants using an improved direct PCR-based technology

Transgenic Research ◽

10.1007/s11248-021-00250-1 ◽

2021 ◽

Author(s):

Anis Ben-Amar ◽

Ahmed Mliki

Keyword(s):

Genetically Engineered ◽

Gene Detection ◽

Direct Pcr ◽

Detection Assay ◽

Genetically Engineered Plants

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The use of chemical and molecular microbial indicators for faecal source identification

Water Science & Technology ◽

10.2166/wst.2003.0155 ◽

2003 ◽

Vol 47 (3) ◽

pp. 39-43 ◽

Cited By ~ 33

Author(s):

B. Gilpin ◽

T. James ◽

F. Nourozi ◽

D. Saunders ◽

P. Scholes ◽

...

Keyword(s):

Direct Pcr ◽

Animal Group ◽

Faecal Pollution ◽

Molecular Assays ◽

Chemical Indicators ◽

Fluorescent Whitening Agents ◽

Feral Animals ◽

Oxidation Ponds ◽

Specific Species ◽

Faecal Sterols

Identifying the source of faecal pollution is important to enable appropriate management of faecal pollution of water. We are developing and evaluating a combination of these microbial and chemical indicators better able to identify the source of faecal pollution. These assays make use of a combination of direct PCR, culturing, and colony hybridisation to identify source specific species of Bifidobacterium, Rhodococcus and Bacteroides. In conjunction with assays for (a) fluorescent whitening agents and (b) faecal sterols and stanols, these indicators were able to identify human derived faecal pollution in river water containing inputs from septic tanks, municipal oxidation ponds, farmed animals and feral animals. Differentiating amongst the animal sources was more difficult and will require development of molecular assays for organisms specific to each animal group.

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