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 Polymerase chain reaction testing is abbreviated PCR. The following discussion of PCR testing is taken from Thomas M. Fleming, Annotation, Admissibility of DNA Identification Evidence, 84 A.L.R.4th 313 (1991), and testimony from the trial, unless otherwise noted. PCR testing is used to increase the amount of the DNA sample. This technique makes DNA testing possible on much smaller samples than RFLP analysis. However, PCR's ability to identify a particular individual to the exclusion of others is much lower. 

In this procedure, DNA is extracted from a sample purified and added to a buffer solution containing chemical primers and an enzyme called ...