Short Tandem Repeat (STR) Profiling
Definition
The amplification and typing of microsatellite loci where short DNA sequences are repeated a variable number of times. When applied to canine or feline nuclear DNA using validated multiplex kits, STR profiling generates a genotype that can individualise an animal within a reference population database.
- Target
- Microsatellite loci, variable repeat number
- Amplification method
- PCR-based multiplex kits
- Species use
- Human and, with validated kits, canine or feline
- Sub-field
- Forensic biology, DNA individualisation
Common questions
Why does veterinary or animal STR profiling need its own validated kits rather than human kits?+
Human STR multiplex kits target loci specific to the human genome, so animal profiling requires separately validated primer sets built for species-specific microsatellite loci and species-appropriate reference population databases.
What role does an animal STR profile play in a forensic case?+
It can link a specific animal, such as a suspect's dog, to trace evidence like hair or saliva at a scene, or confirm ownership and identity in wildlife trafficking or animal cruelty investigations.
How does the statistical strength of an animal STR match compare to a human match?+
Statistical weight depends on the size and genetic diversity of the reference population database for that species and breed, which for many companion animal populations is smaller and less studied than human databases, generally giving a less powerful statistic.
Related terms
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- Canine STR Multiplex
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- Cementum
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- Cryogenic Grinding
- The technique of freezing a tooth sample to cryogenic temperatures (liquid nitrogen, approximately -196°C) before mechanical pulverisation. Freezing prevents frictional heat generation...
- Dentinal Tubules
- Microscopic channels running radially through dentine from the pulp cavity to the outer surface. They house odontoblast cell processes that can carry...
- Medullary Index
- The ratio of the medulla diameter to the total hair shaft diameter. In companion animal hair identification, a medullary index above 0.5...
- Primary Transfer
- The direct movement of biological material from an animal to a surface it contacts. When a dog sheds hair onto its owner's...
- Pulp Extraction
- Accessing the soft tissue of the root canal (pulp) directly by cutting the tooth at the cementoenamel junction and removing the contents...
- Veterinary Forensic Pathology
- The application of post-mortem examination principles to animal deaths where criminal conduct is suspected. A veterinary forensic pathologist documents injuries, assesses cause...
Explained in these topics
- Companion Animal and Veterinary Forensic Biology
- Dental DNA, Tooth Sampling and Molecular IdentificationThe standard nuclear DNA typing method that examines the number of repeated sequence units at a set of polymorphic loci (typically 15-24 in modern commercial k...