Short Tandem Repeat Profiles
Genetic maps of specific genome locations where short base-pair sequences repeat a countable number of times, used to uniquely identify individuals in forensic DNA analysis.
Short tandem repeat profiles are genetic maps identifying specific locations on the genome where short sequences of base pairs repeat a countable number of times. These profiles serve as unique identifiers in forensic science because the repeat counts vary significantly between individuals. They are the foundational data stored in national systems like CODIS to link biological evidence to suspects or exclude innocent persons.
What this means in real life
When a crime scene yields a blood sample, forensic labs extract DNA and measure how many times specific short sequences repeat at 13 standard locations. If those repeat counts match a suspect's profile, it provides strong evidence they were present at the scene.
What it isn’t
This is not a complete genome sequence or a test for genetic diseases. It captures only the number of repeats at a handful of locations, not the actual genetic code or health information—making it ideal for identification without revealing medical details.
Commonly misused online
People often conflate STR profiles with full DNA sequencing or assume they reveal ancestry or health traits. In reality, standard forensic STR panels are deliberately limited to identification markers and reveal almost nothing about heritage or disease risk.