The first step in genotyping is to extract cell samples from a specimen. A deep skin biopsy is used on all specimens. Tissue samples are then incubated in a Petri dish at approximately 95 degrees Celsius before the DNA is extracted. Once extracted, DNA samples are run through an agarose gel rig, which makes the structure of DNA visible under a high-powered microscope.
Genotyping is primarily completed by medical research teams. The process is also done at the collegiate level for medical students with a focus on neurology. Genotyping is a complex procedure, with 15 to 20 steps for each phase. It requires extensive knowledge and experience with lab equipment and sensitive specimens.
Multiple DNA samples are used at one time with genotyping. It is imperative that each sample be kept separate from another, even though they are all tested in close proximity to each other. The slightest cross-contamination will alter the results and make the test useless. The same results must be found repeatedly in order for genotyping results to be deemed accurate.