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Non-STR DNA Markers: SNPs, Y-STRs, LCN and mtDNA

Y-STRs in Forensics

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Y-chromosome specific systems may prove invaluable for the identification of the genetic profile of the male component in mixed male/female specimens, specifically in those instances in which the female portion is present in overwhelming quantities, relative to the male.

Other instances where Y-STRs (Y-Single Tandem Repeats) may be useful are:

  • Deposition of semen by an azoospermic or oligospermic males
  • Cases of oral sodomy where only trace amounts of male buccal epithelial cells may be present
  • Normal post-coital degradative and semen sample loss processes that occur with the passage of time
  • Criminal paternity analysis
  • Disaster victim identification and/or missing person (male individual identified by typing a male relative such as a son, brother, father, nephew, or uncle)

In addition, the ability to specifically detect a male profile could obviate the need for the time-consuming and frequently inefficient differential extraction procedure for the separation of sperm and non-sperm fractions. Male specific systems may also aid in the investigation of cases involving mixtures or degraded DNA specimens (displaying partial autosomal STR profiles) by providing additional statistical discriminating power.

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