Cell line STR genotyping, also known as short tandem repeat (STR) typing, simple repeat (SSR) typing or Microsatellite typing, It detects simple repeats that are widely distributed in eukaryotic genomes. It usually consists of tandem repeats of 2-6bp core sequences, which constitute the genetic polymorphism of STR loci. For a specific individual, the number of repeats at a particular location on the chromosome is fixed, while for different individuals the number of repeats may be different, which constitutes the polymorphism of STR in a population. Due to the large number of such repeats in the human genome, the detection of STR polymorphism can distinguish the differences between individuals and confirm the genetic relationship. STR-PCR has become one of the main methods for gene mapping,screening of target genes and using their polymorphism to study the origin of species. Its application fields include anthropology, genetics, medicine and soon.
STR analysis technology is regarded as the main research goal of individual identification and paternity identification in forensic medicine, and is the core technology of the 2nd generation of forensic DNA fingerprinting technology. Forensic DNA typing (STR composite amplification) has become the main method due to its high sensitivity, small core sequence, and easy to use and has played an important role in the detection of criminal cases and the settlement of civil cases in various countries.