Genetic information may be found in bone, teeth, skin and other soft tissue, tears, sweat, saliva, hair roots, earwax, semen, vaginal fluid, urine and blood. Examples would include saliva on a cigarette butt or drinking glass, or skin cells on a steering wheel or glass. About 95% of human nuclear DNA is non-coding DNA, the so-called 'junk' DNA. These non-coding regions are the areas that are examined in DNA forensic testing (Varsha, 2006). DNA forensic fingerprinting began in Leicester, UK, when in 1984 Alec Jeffreys discovered hypervarible loci made up of approximately 10 to 1000 tandemly repeated sequences, each typically 10-100 base pairs in length (Gill et al., 1985; Jeffreys et al., 1985a, 1985b). Applications of molecular DNA analysis include criminal, immigration and civil cases. Murder, assault, rape, paternity testing and family and body identification are all issues that can be addressed with these techniques.
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