Biotechnology tools have revolutionized forensic sciences by enabling analysis of biological evidence. Restriction fragment length polymorphism was an early technique using Southern blotting for DNA fingerprinting. Polymerase chain reaction is now preferred as it amplifies DNA, is sensitive, and requires less work. Other techniques profile mitochondrial DNA, Y-chromosomes, microsatellites, and Alu repeats to identify suspects, examine lineages, and study populations. Applications include sample analysis, lineage tracing, suspect identification, anthropology, and population genetics. Biotechnology continues advancing forensic sciences capabilities.

1. Biotechnology in Forensic Sciences
Zahra Naz
(MPHIL-BT-28)
National Institute for Biotechnology and Genetic Engineering, Faisalabad, Pakistan

2. Biotechnology
“Any technological application that uses
biological systems, living organisms, or
derivatives thereof, to make or modify
products or processes for specific use”
Convention on Biological Diversity
https://www.cbd.int/convention/text/
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3. Forensic sciences
“Forensic sciences involve the scientific
analysis and documentation of evidence
suitable for legal proceedings”
Hamilton County Forensic Center, USA.
https://foursquare.com/v/hamilton-county-forensic-center/4cc9bc05786e4688d0ee9509
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4. History of Biotechnology in Forensics
RFLP technology: By Southern in 1975
DNA analysis/ Fingerprinting/ Typing/ Profiling
DNA analysis initiated in mid-1980s
Dr. Alec Jeffreys credited RFLP for forensic purposes
V. V. Pillay, R. G. Menezes, R. Krishnaprasad, M. Pillay, S. W. Lobo, D. Adhikari, P. Vishwanath, N. B. Bhat, T. Kanchan and D. M.
Vasudevan, Biotechnology in forensic science: the revolution continues, Nepal Med Coll J, 9.2007, 57-62.
Dr. Alec Jeffreys-1950
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5. Tools of Biotechnology in Forensic Sciences
Restriction Fragment Length Polymorphism
Polymerase Chain Reaction
Random Amplified Polymorphic DNA
Inter Simple Sequence Repeats analysis
Mitochondrial DNA analysis
Y chromosome markers analysis
Alu repeats analysis
American Prosecutors Research Institute, USA.
Forensic DNA Fundamentals for the Prosecutor: http://www.nsvrc.org/organizations/2436/18/2017 5

6. Restriction Fragment Length Polymorphism (RFLP)
• Based on hypervariable DNA region restriction
• Southern blotting
• RFLP- finger print
• Individual identification
Biotechnology and Forensic Science – Advanced
http://www.ck12.org/book/ck-12-biology-advanced-concepts/section
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7. Polymerase Chain Reaction (PCR)
• DNA amplification
• Biological parent identification
• Preferred due to availability of kits,
sensitivity and less labor input
N. Morling, PCR in forensic genetics, Biochemical Society Transactions, 37.2009, 438-440.6/18/2017 7

8. Random Amplified Polymorphic DNA (RAPD)
• Use of non-specific primers to amplify many regions of a sample DNA
• Can amplify upto 100 or more loci in one sample
• Special importance in the entomological investigations of corpses
L. Congiu, M. Chicca, R. Cella, R. Rossi and G. Bernacchia, The use of random amplified polymorphic DNA (RAPD) markers to identify
strawberry varieties: a forensic application, Mol Ecol, 9.2000, 229-32.
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9. Inter Simple Sequence Repeats analysis
• Based on microsatellite primers
• No prior genomic information required
• Highly sensitive and informative
Bornet B, Branchard M. (2001) Non-anchored inter simple sequence repeat (ISSR) markers: Reproducible and
specific tools for genome fingerprinting. Plant Mol Biol Reporter 2001; 19: 209-15.
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10. Mitochondrial DNA analysis
Preferred due to
• High copy number
• Lack of recombination
• Only maternal lineage identification
Wilson MR, DiZinno JA, Polanskey D, Replogle J, Budowle B. Validation of mitochondrial DNA sequencing for
forensic casework analysis. Int’l J Legal Med 1995; 108: 68-74.
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11. Y chromosome markers
• For gender discrimination
• Identity fixation in rape cases
• For paternal lineage analysis
Jobling MA, Pandya A, Tyler-Smith C. The Y-chromosome in forensic analysis and paternity testing. Int’l J Legal
Med 1997; 110: 118-24.
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12. Alu repeats analysis
• Transposable elements
• Site for Arthrobacter luteus (Alu) restriction endonuclease
• Can be present/absent on same chromosome among different families
• Identification of population ancestral lineage
Scott Watkins W, Rogers AR, Ostler CT et al. Genetic variation among world populations: Inferences from 100 Alu
insertion polymorphisms. Genome Res 2003; 13: 1607-18.
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13. Applications
• Sample analysis
• Lineage analysis
• Suspect identification
• Anthropological studies
• Population genetics studies
V. V. Pillay, R. G. Menezes, R. Krishnaprasad, M. Pillay, S. W. Lobo, D. Adhikari, P. Vishwanath, N. B. Bhat, T. Kanchan and D. M.
Vasudevan, Biotechnology in forensic science: the revolution continues, Nepal Med Coll J, 9.2007, 57-62.
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