Advanced screening
Serological screening is often the first step in forensic DNA testing. Our trained serologists are trained to screen evidence for the presence of bodily fluids, such as blood, menstrual blood, urine, saliva, and semen. Using specialized chemical and microscopic tests, we identify the presence of these fluids and preserve the evidence for downstream DNA analysis.
Even the smallest trace of biological material can yield a useable DNA profile with the advanced technologies in our DNA Toolbox™ such as Forensic Investigative Genetic Genealogy (FIGG) or Next Generation Sequencing (NGS). Our lab’s meticulous approach ensures sensitive detection and optimal results, even in degraded or minimal samples. DNA can be extracted from minute traces of human biological material for profiling.
Serology methods at DLI
Blood, saliva, semen, menstrual blood, and urine.
- For the detection of semen, the analyst has the option of using any or all of the following:
- Alternate light source (ALS) examination
- Brentamine test for acid phosphatase
- Combo p30 ABAcard/amylase card
- Microscopic examination of sperm cells with the Christmas tree stain
Serology methods at DLI
- For the detection of blood, the analyst will perform a visual examination and perform presumptive blood testing using TMB and/or Kastle-Meyer (phenolphthalein).
- For the detection of saliva, the analyst will use RSID™ – saliva test devices for the presence of human α-amylase.
- Uritrace for presumptive urine and
- Seratac PMB for presumptive menstrual blood testing and peripheral blood.
Screening Techniques
- SPENTSHELL® – proprietary screening method for fired shell casings and other non-porous substrates.
- M-Vac – a wet vacuum system highly effective for recovering trace DNA from clothing, any other porous surfaces, and liquids.
- Bone Protocol – three proprietary methods for prepping bones.
