PCR (Polymerase Chain Reaction)
Definition
A method for amplifying specific DNA sequences from very small or degraded samples, developed by Kary Mullis in 1983. PCR made DNA profiling feasible from trace evidence, including single hairs, touch DNA, and aged bloodstains. It forms the basis of all modern forensic STR and other profiling methods.
Related terms
- ABO blood group system
- Classification of red blood cells by the presence or absence of A and B antigens on the cell membrane, determined by alleles...
- Mitochondrial DNA (mtDNA)
- DNA located in mitochondria rather than the cell nucleus. Present in hundreds to thousands of copies per cell, making it recoverable from...
- RFLP (restriction fragment length polymorphism)
- The first DNA profiling method used in forensic casework, developed by Alec Jeffreys in 1984. Restriction enzymes cut DNA at specific sequences,...
- STR (short tandem repeat)
- A genomic locus where a 2, 7 base-pair unit is repeated in tandem a variable number of times between individuals. The variation...
- Touch DNA
- Minute quantities of epithelial cells transferred by skin contact with a surface, without leaving a visible stain. Collected by swabbing contact points...
Explained in
- History and Development of Forensic BiologyA method for amplifying specific DNA sequences from very small or degraded samples, developed by Kary Mullis in 1983. PCR made DNA profiling feasible from trac...