Fundamentals of Autosomal STR Typing for Forensic Applications: Case Studies

Each human has 23 pairs of chromosomes, out of which 22 pairs are autosomes and 1 pair is sex chromosome. These 22 pairs of autosomes which determine somatic characters of an individual contribute to the unique genetic makeup of an individual which are inherited from its parents. In this regard, autosomal STRs present at the surrounding of the centromere of an autosomal chromosome are of high use due to their usability in generating a unique fingerprint in an individual. The usefulness of STRs as popular DNA markers relies on the fact that they can be amplified easily by polymerase chain reaction (PCR) and the single copy STR inheritance from each parent. Additionally, the highly variable nature of a number of STR repeats among individuals makes STRs effective for genetic identification of individuals. In this chapter, various autosomal STR markers and their usefulness in the criminal justice system have been discussed in detail.