Short tandem repeat (STR)
Definition
Short repetitive DNA sequences scattered throughout the genome, with the number of repeats varying between individuals at each locus. DNA profiling compares repeat counts at multiple STR loci simultaneously, producing a profile whose random match probability is typically below one in a billion for a full panel.
Related terms
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- Locus (plural: loci)
- A defined physical position on a chromosome. In forensic genetics, 'locus' usually refers to a specific STR site used in profiling. The...
Explained in these topics
- Blood as Biological EvidenceRepetitive DNA sequences at defined chromosomal loci that vary in the number of repeat units between individuals. Forensic STR profiling compares allele length...
- Chromosomes, Genes and the Human GenomeA DNA sequence consisting of a short motif (typically 2 to 6 base pairs) repeated in tandem multiple times. The number of repeats varies between individuals, m...
- Hair as a Source of DNA and Toxicological InformationRepetitive sequence motifs at specific chromosomal loci used for nuclear DNA profiling. STR profiles are individual-specific (except in identical twins) and ar...
- The Transition from Serology to DNA Profiling in Forensic ScienceShort repetitive DNA sequences scattered throughout the genome, with the number of repeats varying between individuals at each locus. DNA profiling compares re...