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Due to their abundance and relative ease of genotyping, single nucleotide polymorphisms (SNPs) are a commonly used molecular marker for contemporary population genetic and genomic studies. A high-density and cost-effective way to type SNP loci is Allegro targeted genotyping (ATG), which is a form of targeted genotyping by sequencing developed and offered by Tecan genomics. One major drawback of this technology is the need for a reference genome and information on SNP loci when designing a SNP assay. However, for some non-model species genomic information from other closely related species can be used. Here we describe our process of developing an ATG assay to target 50,000 SNPs in Rocky Mountain bighorn sheep, using a reference genome from domestic sheep and SNP resources from prior bighorn sheep studies. We successfully developed a high accuracy, high-density, and relatively low-cost SNP assay for genotyping Rocky Mountain bighorn sheep that genotyped ~45,000 SNP loci. These loci were relatively evenly distributed throughout the genome. Furthermore, the assay produced genotypes at tens of thousands of SNP loci when tested on other mountain sheep species and subspecies.

An efficient method for analyzing illegal and medicinal drugs in whole blood using fully automated sample preparation and short ultra-high-performance liquid chromatography–tandem mass spectrometry (MS/MS) run time is presented. A selection of 31 drugs, including amphetamines, cocaine, opioids, and benzodiazepines, was used. In order to increase the efficiency of routine analysis, a robotic system based on automated liquid handling and capable of handling all unit operation for sample preparation was built on a Freedom Evo 200 platform with several add-ons from Tecan and third-party vendors. Solid-phase extraction was performed using Strata X-C plates. Extraction time for 96 samples was less than 3 h. Chromatography was performed using an ACQUITY UPLC system (Waters Corporation, Milford, USA). Analytes were separated on a 100 mm × 2.1 mm, 1.7 μm Acquity UPLC CSH C 18 column using a 6.5 min 0.1 % ammonia (25 %) in water/0.1 % ammonia (25 %) in methanol gradient and quantified by MS/MS (Waters Quattro Premier XE) in multiple-reaction monitoring mode. Full validation, including linearity, precision and trueness, matrix effect, ion suppression/enhancement of co-eluting analytes, recovery, and specificity, was performed. The method was employed successfully in the laboratory and used for routine analysis of forensic material. In combination with tetrahydrocannabinol analysis, the method covered 96 % of cases involving driving under the influence of drugs. The manual labor involved in preparing blood samples, solvents, etc., was reduced to a half an hour per batch. The automated sample preparation setup also minimized human exposure to hazardous materials, provided highly improved ergonomics, and eliminated manual pipetting. Figure Robotic setup for fully automated solid-phase extraction of whole blood

Using highly accurate photo-chemical machining or photo-electroforming, mesh membranes can be produced as flat sheets, as flexible membranes, or in three-dimensional forms. The screens are said to be easy to clean, are extremely durable, and can have various surface textures - such as bright, semi-bright, matt, smooth or brushed. The production techniques are claimed to be so accurate that hole sizes can be as small as six microns across, and edge definition can be to within one micron.

This chapter focuses on the DNA extraction process and also covers assessment of DNA quantity and quality prior to sample processing. The goals of the DNA extraction process are typically to lyse cells to release the DNA molecules, separate the DNA molecules from other cellular material, and isolate the DNA into a format compatible with downstream applications including polymerase chain reaction (PCR) amplification. The quantity and quality of DNA often need to be measured prior to proceeding further with analytical procedures to ensure optimal results. All samples are carefully handled regardless of the DNA extraction method to avoid sample-to-sample contamination or introduction of extraneous DNA. The extraction process is where the DNA sample is more susceptible to contamination in the laboratory than at any other time in the forensic DNA analysis process. For this reason, laboratories usually process the evidence samples at separate times and sometimes even different locations from the reference samples. There are several primary techniques for DNA extraction used in today's forensic DNA laboratory: organic extraction, Chelex extraction, and FTA or solid–phase extraction. The exact extraction or DNA isolation procedure varies depending on the type of biological evidence being examined.