What is the DNA Profiling Procedure?
Maxxam’s laboratory procedure is based on state-of-the-art polymerase chain reaction (PCR) technology and employs three major steps: DNA extraction, amplification and electrophoresis. Extraction involves the removal and purification of DNA from a biological sample. This is accomplished by chemical treatment which ruptures cells and separates DNA from other unwanted cellular components. Once extracted, a thermostable enzyme, specifically designed DNA primers and a machine called a thermocycler are used to replicate (amplify) targeted regions of the DNA molecule. The targeted regions are those which are highly variable from person to person. This variation in the DNA is the result of variable numbers of short tandem repeats (STRs) that give rise to amplified fragments that vary with respect to their length. Multiple cycles of this amplification step are performed which results in the production of millions of copies of each STR. In this way, the PCR process enzymatically generates millio
