LITTLE KNOWN ASPECTS OF DNA ANALYSIS
STRs: Short Tandem Repeats. Currently the state of the art DNA analysis, this is fast, greatly automated, and exclusionary, meaning that it can eliminate a greater number of people than RFLP can, under most circumstances. The results will show up as a graph on a computer screen.
Mitrochondrial: This is a different type of DNA than is used in the above samples. It is a circular plasmid found in mitochondria, which are kidney-bean shaped organelles in the cell. It can be obtained from fingernails, hair, and other dead cells from which it is difficult to get nuclear DNA. This analysis is delicate and problematic; the FBI does most mitochondrial analysis at the moment, although this will change in the future, as forensic labs continue to attract funding. Mitochondrial DNA is passed down unchanged from mother to child, so that a person's siblings, mother, maternal aunts and uncles, and a cousin by a maternal aunt (you get the picture) would have identical mitochondrial DNA. Therefore, aha, the killer may not be Poindexter but his cousin, Bradley.
Statistics: Although a murder could easily be committed over the controversy surrounding population genetics and their interpretation, I would suggest you avoid the whole subject. Unless you are a mathematician.
Personnel: DNA analysis used to be performed by forensic lab personnel who were trained in the procedure. Today's DNA analyst is more likely someone with a degree in genetics and/or DNA analysis, often from a university research program. The result is a forensic DNA expert who has no prior exposure to forensics or law enforcement. Culture shock, anyone?
Billing: DNA analysis is expensive. Labs charge big dollars, but not to be greedy; the equipment and supplies necessary are pricey items. $600-$1000 per sample is not unreasonable, and the most simple of cases will require two or three:the evidence bloodstain, the suspect's blood sample, and the victim's blood sample. It would not be surprising to find that each lab system has its own standards for billing. At our lab, DNA analysis was included if we performed the autopsy (including out-of-county cases). Of course, just because a police department submitted 50 samples did not mean that we would analyze all 50. In practical terms, the prosecution would get what they wanted and the defense had no say in the process. Most labs try to be strictly fair to both prosecution and defense; however, there has to be a continual struggle between what
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