Review of Forensic DNA Biology: A Laboratory ... - ACS Publications

Aug 27, 2013 - The scientific community, and particularly forensic biology, has experienced rapid evolution because of the advent of new technologies ...
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Review of Forensic DNA Biology: A Laboratory Manual Reena Roy* Forensic Sciences Program, Eberly College of Science, Pennsylvania State University, University Park, Pennsylvania 16802, United States There are other methods, all presumptive at this time, to detect amylase in body fluids such as in saliva, or Tamm-Horsefall protein in urine. The same is true about fecal matter. Microscopic examination of fecal matter can yield several interesting features. Chapters describing DNA extraction, gel electrophoresis, quantitation of extracted DNA, polymerase chain reaction (PCR) technology involved in multiplex reactions, and capillary electrophoresis are fairly easy to follow. Other chapters deal with Y-STR polymorphism, missing person cases, paternity testing, and statistics. The author has included other currently explored technology such as Sequence for Cloning (Chapter 20). The chapter titled “Low Copy Number Stochastic Results” describes the analysis of low template DNA. The book also includes DNA analysis of botanical material (Chapter 21). Using Cannabis sativa (marijuana) as an example is a good idea, as this is the most common plant forensic drug chemists or biologists encounter in their careers. Use of this plant for medical purposes also increases the chance that it will be included as evidence collected at crime scenes. The procedure that generates a PCR product unique to marijuana is helpful to a forensic scientist. Other methods, including commercial products available for the detection of this commonly used drug, are useful. The book also includes detection of single nucleotide polymorphism with mitochondrial DNA analysis. Extraction of ribonucleic acid is also included and explained. The analysis of ribonucleic acid and mitochondrial DNA is not commonly used in state or local crime laboratories. However, these chapters expose the students to the two different types of analysis not common in forensic casework. The book also includes chapters on population databases and use of BioEdit for analyzing DNA sequence data, helpful for probability calculations. Determination of quality and quantity of DNA yield is essential; on this topic, the author goes into excellent detail. That is also true about the use of UV−vis spectroscopy, fluorescence spectroscopy, and real-time PCR to determine quality and quantity of DNA. However, instruments such as 7500 RT PCR, Plexor, or Rotor-Gene are not described with protocols. Most forensic crime laboratories use one of these or similar instruments for detecting the amount of yield from evidence samples. Computers and computer simulations are now routinely used in forensic science, which the author has described well. In silico labs describing how to calculate paternity or for a missing person case using statistics is a great idea for training. Primer design (in silico) is described in Chapter 9. This includes, but is not limited to, background, NCBI, accession numbers, the 13 Core CODIS loci, and the

Forensic DNA Biology: A Laboratory Manual by Kelly M. Elkins The Academic Press, an imprint of Elsevier: Oxford, U.K. and Waltham, MA, 2013. 198 pp. ISBN-978-0123945853 (softcover). $49.95.

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he scientific community, and particularly forensic biology, has experienced rapid evolution because of the advent of new technologies in the field of molecular biology. DNA profiling has become the gold standard in the legal justice system. Each method instituted in crime laboratories in the United States must follow the Federal Bureau of Investigation quality assurance standards. These standards are used for the audit of the forensic DNA and convicted offender DNA databasing laboratories. The magnitude and power of DNA analysis technique relies on high discrimination potential. Each technology used in DNA analysis must be subjected to peer review prior to publication, and each procedure must go through extensive validation in individual forensic DNA testing laboratory before casework analysis. Laboratories must independently establish quality assurance and quality control measures in place, and determine an interpretation threshold. Methods involving touch DNA evidence use low template DNA. The potential for obtaining DNA profiles from a very low level of DNA is enormous and techniques for handling low copy number (LCN) DNA are being instituted in some laboratories. Rapid growth in the area of next generation sequencing (NGS) and instruments developed by companies such as IntengenX and others are gaining momentum. With the use of instruments such as RapidHIT, DNA profiles can be generated directly at the police station by nonscientists. These and other instruments such as BioMark HD System make genetic analysis faster and simpler. The author of Forensic DNA Biology, A Laboratory Manual includes laboratory experiments and procedures supposedly employed by regional, state, and federal crime laboratories. The book consists of 22 chapters, with several chapters on forensic DNA analysis and its application. Only one chapter is devoted to forensic serology, and it describes identification of body fluids. The author goes to great lengths to list the components of each body fluid but does not describe the principles, limitations, and so forth of each presumptive or confirmatory test in detail. Preparing a forensic analyst to testify is part of the training process. One of the most important functions an analyst performs is to detect body fluids so that evidence can be subjected to DNA analysis. The protocols for the body fluid identification could have been made clearer in this book. Because none of photographs that indicate the results of the presumptive and confirmatory tests are in color, the impact is less than it could have been. The author describes the Phadebas test but does not describe other tests for the presumptive detection of saliva. Only one test is described for urine analysis. © 2013 American Chemical Society and Division of Chemical Education, Inc.

Published: August 27, 2013 1265

dx.doi.org/10.1021/ed400437w | J. Chem. Educ. 2013, 90, 1265−1266

Journal of Chemical Education

Book and Media Review

procedures for creating a multiplex of two primer sets for two unique sites on DNA. Multiplex reactions using PCR primers are described with procedures for use. This is not a method commonly practiced in crime laboratories, yet it would be useful for students preparing for a career in forensic DNA analysis. Commercial kits along with the 310 Genetic Analyzer from ABI, a single capillary instrument, is included in the manual. Computation of DNA and random match probability using a population database is also explained. However, students or trainees not familiar with the thermal cyclers may not understand what “repeat the above cycle 28 times” means. Steps in the thermal cycling process could have been broken down differently, such as steps for denature, anneal, extension, and hold. The chapter dealing with “Social, Ethical and Regulatory Concerns” describes some relevant and interesting topics, including privacy, ownership of genetic information, and issues regarding collection and retention of body fluids. “Abandoned Property” deals with the collection of samples, which are found at crime scenes and other places. The three distinct points of view regarding genetic evidence are termed “genetic exceptionalism, genetic minimalism, and biological pragmatism”. These issues might have been described more concisely for the benefit of new analysts. Instead of words such as “recipes”, it would have been better to use scientific language, such as “formula” in the book. For a student unfamiliar with many of the modern DNA terms such as STR, SNP, SWGDAM, and so on, it would have been better to include these terms in a glossary format at the beginning of the book or at least before each chapter. For example, when using the word “druggist’s fold”, it should be described what a druggist fold is and how to create one. Some of the sentences could have been phrased more clearly. Page 32 describes tissues (body, plant). Does this mean human (animal) tissues or plant material such as stems, leaves, and so forth? Or, does this extraction method cover both human tissues and plant material? The same is true for hair. It would be useful to indicate that roots might not be present or that after examining hairs by microscopy, samples can be analyzed for both STR (when root present) and mitochondrial DNA when only the shaft is present. Questions at the end of each chapter are excellent, but do the students or trainees have access to the answers? While the book is intended for forensic crime laboratories, the protocols are not detailed enough for use in the legal system. The manual is better suited for academic laboratories.



AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Notes

The authors declare no competing financial interest.

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dx.doi.org/10.1021/ed400437w | J. Chem. Educ. 2013, 90, 1265−1266