Southern Association of Forensic Scientists
2018 Annual Meeting
Introducing the QuantStudio™ 5 Real-Time PCR System and the HID Real-Time PCR Analysis Software v1.3 including the Virtual Standard Curve: The latest addition to our human identification (HID) real-time PCR family of offerings
Presenter(s): Life Technology Staff
Workshop topic(s): Do you know what the camera in your phone and the new real-time PCR instrument, the QuantStudio 5 may have in common? This workshop is designed to introduce and discuss the latest qPCR instrument and software offerings by Thermo Fisher Scientific. In this workshop, and you will learn how this system can seamlessly be introduced to your laboratory, how it differs from the 7500 Real-Time PCR Instrument, and how the use of the new Virtual Standard Curve functionality provided in the HID Real-Time Software v1.3 can save your lab in time and decrease run to run variation. We will change gears a bit and wrap up this half-day workshop with a quick discussion of our lessons learned since the release of the GlobalFiler™ PCR Amplification in 2013.
This workshop will cover:
- A hands-on introduction of the QuantStudio 5 Real-Time PCR System
- The Virtual Standard Curve: how it works, things to consider, & how it may benefit your lab
- The customer experience: using the Quantifiler™ Trio Quantification Kit with new functionality
- The GlobalFiler Kit: what we know after 4 years in the field
The Future of Forensic Genomics is Now
Presenter(s): Melissa Kotkin (Verogen, Inc. 11111 Flintkote Avenue, San Diego, CA 92121, USA)
Workshop topic(s): The combination of Short Tandem Repeat (STR) markers and Capillary Electrophoresis (CE) detection methods has established DNA testing at the center of modern criminal investigations. Although the methods have become more sophisticated, the fundamentals of the systems have changed little in the last decade. The increasing need for more comprehensive data from decreasing quantities and qualities of DNA evidence is exceeding the fixed capability of CE platforms and current interpretation methods to reach conclusive results. In an effort to overcome current limitations, forensic scientists worldwide are now investigating the value of Next-generation Sequencing (NGS) for forensic applications. Illumina’s decade-proven sequencing by synthesis (SBS) technology offers a massively parallel approach for simple and accurate sequencing of large numbers of PCR amplicons in a single reaction. This offers new opportunities for taking methods currently employed in clinical and research settings and applying them to routine forensic analysis in operational casework laboratories. In this Workshop, we will examine the limitations of current DNA testing methods and the specific benefits of the sequencing by synthesis approach for forensic analysis. We describe how developmentally validated instrument, chemistry and software solutions result in NGS now becoming a viable alternative to current CE-based methods for routine forensic casework applications. We will also demonstrate how, by delivering data that span the genome to capture more forensically relevant markers, NGS can answer a wider range of questions in a single, targeted assay. This approach offers a variety of key improvements including relieving analysis limitations associated with challenging samples such as complex mixtures, flattening the analyst’s decision tree and reducing workflow complexity compared to current methods.
What’s New on the Designer Drug Scene (Emerging Drugs and their MS Interpretation)
Presenter(s): Donna M. Iula, Ph.D. (Cayman Chemical)
Workshop topic(s): The designer drug landscape is ever shifting and it’s a constant battle for drug chemists to be able to detect the latest designer drugs on the scene. The goal of this workshop is to learn about topics such as:
- New analogues being trafficked and spectroscopic tips/techniques for their detection.
- How might clandestine chemists be synthesizing the newest designer drugs and what might
- What is known about the metabolism of prevalent designer-drug classes?
Sample Preparation, Purification and Isolation for Unusual or Difficult Samples, including Fentanyl
Presenter(s): Tim McKibben (Synthcon)
Workshop topic(s): This workshop will cover sample preparation for unusual or difficult samples. Chemists are very familiar with traditional sample preparations, but what do you do when the sample is a half-eat food item, a semi-solid, or something that becomes tacky upon exposure to air. How do you isolate a drug from other interfering components? Procedures to deal with these “nasty” sample matrices will be covered along with real case examples where the sample matrix issue was solved through certain preparation techniques. Additional tips and tricks will be included to assist the chemist when trying to handle and prepare such samples. Finally some tips on preparing fentanyl samples will also be discussed.
Infrared Analysis for Drug and Trace Chemists
Presenter(s): Jeremiah Morris (Johnson County Sheriff’s Office Criminalistics Laboratory)
Workshop topic(s): This workshop will provide a brief review of the theory of infrared spectroscopy. Topics to be covered include how infrared light interacts with molecules, different forms of vibrations and how these vibrations appear in an infrared spectrum, sample handling and analysis factors which can affect the resultant spectrum, and what structural information can be obtained from the infrared spectrum of an unknown substance. Additional topics may include polymorphs, differentiation between structurally similar compounds, and criteria to determine when a known and unknown spectra “match”.
Predicaments and Perplexities Due to Prevalence Of Emerging Substances in Drug Chemistry Casework, and Portable Possibilities For Presumptive Identification
More info coming soon
Presenter(s): Nancy McCombs (fateforensicinstruction.com)
- To familiarize the students with the importance of understanding the history of subclass characteristics in the literature.
- To examine commonly used methods used in machining firearm components/tools and evaluate them for subclass potential.
- To introduce students to methods of recognizing potential subclass characteristics.
- To provide students with examples of documenting potential subclass characteristics.
- To provide students with formal training in “Subclass Characteristics” to assist in strengthening future expert witness testimony.
Addressing Bias in Forensic Examinations (cognitive bias)
Presenter(s): Jeremiah Morris (Johnson County Sheriff’s Office Criminalistics Laboratory)
Workshop topic(s): Scientific disciplines have long recognized the influence bias has upon both analytical testing as well as interpretation of the results from this testing. Although the majority of scientific and medical disciplines have recognized the potential for bias and have incorporated procedures to minimize the affect bias has upon the ultimately conclusions, crime labs have generally not addressed bias in their examinations. This workshop will provide an introduction into the mind of the expert, how we make decisions, how we process information, mental shortcuts our mind uses, and four major categories of bias ‐ motivational, expectation, contextual, and confirmatory bias. The workshop will demonstrate how these forms of bias can adversely affect the forensic process from crime scene collection to courtroom testimony. The workshop will also provide possible solutions to assist in minimizing the affect bias ultimately has upon the conclusions made by forensic scientists.
Validation of Analytical Methods in Forensic Toxicology
Presenter(s): Marc A. LeBeau, PhD, F-ABFT (FBI Laboratory Quantico, VA)
Workshop topic(s): Validation is the process of performing a set of experiments that reliably estimates the efficacy, reliability, and reproducibility of an analytical method. The goal of conducting validation experiments is to establish evidence which demonstrates that a method is capable of successfully performing at the level of its intended use and to identify the method’s limitations under normal operating conditions.
A survey of the literature finds there are numerous approaches used to demonstrate that a method is “valid”, yet they differ in their level of thoroughness. This suggests that some approaches are insufficient while others may be overly rigorous. In 2012, the Scientific Working Group for Forensic Toxicology (SWGTOX) published a minimum standard of practice for the validation of analytical methods used in forensic toxicology. Since then, the ownership of the standard was taken over by the Organization of Scientific Area Committee’s (OSAC) Toxicology Subcommittee. A few updates were implemented before release to the general public in late 2017 through the AAFS Standards Body (ASB).
This session will discuss the requirements of the SWGTOX/OSAC/ASB validation standard. It will include the topics of a) establishing a validation plan based on the intended use of the method, b) designing experiments for critical validation parameters (bias and precision, calibration model, interferences, limit of detection and limit of quantitation), c) how to efficiently conduct validation experiments, and d) knowing when revalidation is needed.
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