STR analysis

Short tandem repeat (STR) analysis on a simplified model using polymerase chain reaction (PCR): First, a DNA sample undergoes PCR with primers targeting certain STRs (which vary in lengths between individuals and their alleles). The resultant fragments are separated by size (such as electrophoresis).[1]
A partial human STR profile obtained using the Applied Biosystems Identifiler kit

Short tandem repeat (STR) analysis is a common molecular biology method used to compare allele repeats at specific loci in DNA between two or more samples. A short tandem repeat is a microsatellite with repeat units that are 2 to 7 base pairs in length, with the number of repeats varying among individuals, making STRs effective for human identification purposes.[2] This method differs from restriction fragment length polymorphism analysis (RFLP) since STR analysis does not cut the DNA with restriction enzymes. Instead, polymerase chain reaction (PCR) is employed to discover the lengths of the short tandem repeats based on the length of the PCR product.

  1. ^ Image by Mikael Häggström, MD, using following source image: Figure 1 - available via license: Creative Commons Attribution 4.0 International", from the following article:
    Roberta Sitnik, Margareth Afonso Torres, Nydia Strachman Bacal, João Renato Rebello Pinho (2006). "Using PCR for molecular monitoring of post-transplantation chimerism". Einstein (Sao Paulo). 4 (2).{{cite journal}}: CS1 maint: multiple names: authors list (link)
  2. ^ Butler, John M. (4 August 2011). Advanced Topics in Forensic DNA Typing: Methodology. San Diego: Elsevier Academic Press. pp. 99–100. ISBN 9780123745132.