RAPD (Randomly Amplified Polymorphic DNA)
Definition
A PCR technique using short arbitrary primers (8-10 bases) that bind at multiple sites across a genome, generating a fingerprint pattern of bands. Used in the 1992 Bogan paloverde case. Sensitive to protocol variation; largely replaced by microsatellite and SNP approaches in modern plant forensics.
- Primer length
- 8 to 10 bases
- Technique type
- PCR-based DNA fingerprinting
- Modern replacements
- Microsatellite and SNP profiling
Common questions
How does RAPD create a DNA fingerprint?+
RAPD uses short arbitrary primers, typically 8-10 bases long, that bind at multiple sites across a genome. During PCR amplification, these primers generate a pattern of DNA bands. This band pattern serves as a DNA fingerprint that can be compared between samples.
Why has RAPD been largely abandoned in modern forensics?+
RAPD is highly sensitive to small variations in experimental conditions and protocol. This inconsistency made it unreliable for casework. Modern methods like microsatellite analysis and SNP profiling produce more reproducible and standardized results, making them preferred for forensic DNA identification today.
What was the significance of the paloverde case?+
The 1992 paloverde case was an application of RAPD to plant DNA forensics, demonstrating that RAPD could be used to link botanical evidence to a suspect in a criminal investigation.
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Explained in these topics
- Plant DNA, the Paloverde-Seed Case and the Diatom Test in DrowningA PCR technique using short arbitrary primers (8-10 bases) that bind at multiple sites across a genome, generating a fingerprint pattern of bands. Used in the...
- The Palo Verde Seed CaseA PCR-based method that uses a single short arbitrary primer to amplify multiple anonymous loci across the genome simultaneously. The banding pattern on a gel...