Forensic Biology & DNA
Biological Screening
The ability to locate pertinent biological material during evidence examination is the most important part of the DNA analysis process. In many cases, our analysts identify key biological material that has been often overlooked by other agencies.
Our analysts use an unbiased case-informed approach to focus on relevant items or areas of evidence and specialize in the analysis of minimal, aged, and degraded DNA. This rigorous approach is a major factor behind our consistent success, even in cases where other labs have fallen short.
When you submit evidence to us, you can be confident it will be thoroughly examined and receive the highest level of care and expertise.
The Importance of STR DNA Analysis in Modern Forensics
Approximately 99.9% of our DNA is identical to every other human being who has ever lived, the remaining 0.1%—the small but crucial portion that varies between individuals (except identical twins)— gives each of us our unique traits, such as height, skin, hair and eye color, and curly or straight hair.
Forensic DNA analysis targets other DNA variations in this 0.1%, called Short Tandem Repeats (STRs), to determine, for example, the likelihood that a biological stain (such as blood or semen) from an evidence item originated from a person of interest.
Forensic scientists use a technique called polymerase chain reaction (PCR), to amplify or generate billions of copies of these STR markers so they can be detected and interpreted.
Forensic DNA Typing
We use state-of-the-art DNA technology in forensic DNA typing to maximize the amount of information from biological material, which includes:
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Autosomal STR Analysis using GlobalFiler™ and Investigator® 24plex
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Y-Chromosome STR Analysis using Yfiler™ Plus
Interpreting Complex DNA Mixtures with STRmix™ Probabilistic Genotyping
FACL uses STRmix™ Probabilistic Genotyping Software to interpret autosomal DNA profiles. As forensic DNA technology has evolved over the last three decades it has improved our ability to detect complex mixed DNA samples involving multiple individuals, often from low-level or degraded sources. STRmix™ allows interpretation of complex DNA results with enhanced accuracy and consistency.
While STRmix™ is a powerful tool, it is not a “black box.” Expert interpretation remains essential. Our DNA analysts understand how the software interprets a profile and how to evaluate diagnostics to ensure reliable results. The correct use of probabilistic genotyping requires training, experience, and careful scientific judgment.
At FACL, your evidence will be interpreted by highly trained professionals with extensive expertise in both traditional and probabilistic DNA analysis. Our rigorous approach ensures results that are scientifically sound, defensible, and clearly communicated.
Accreditation
Our laboratory adheres to a strict quality assurance/quality control program. Our Forensic Biology and DNA section is accredited by ANAB to the current ISO/IEC 17025 international standard and FBI QAS for biological screening and autosomal and Y-chromosome STR analysis in forensic casework.
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