The S. salivarius is chosen because it the predominant gram positive bacteria that colonizes the oral cavity shortly after birth.
Polymerase chain reaction(PCR) test is a type of test that is used to identify a particular deoxyribonucleic acid of an organism.
Streptococcus salivarius cannot be cultured especially when the test sample is contaminated with other body normal flora.
The steps of PCR testing include the following:
On a crime scene, the specimen that can be used for PCR testing are blood and body secretions.
PCR testing can be done on a scene with blood spills.
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