The DNA alphabet is made up of four building blocks – A, C, T and G, called base pairs, which are linked together in long chains to spell out the genetic words, or genes, which tell our cells what to do. The order in which these 4 DNA letters are used determines the meaning (function) of the words, or genes, that they spell.
DNA fingerprints finger prints from 6 different people (1 in each column)DNA can be cut into shorter pieces by enzymes called restriction endonucleases. The pieces can then be separated according to there size on a gel.
Human DNA is 99% identical between individuals, but the 1% that differs enables scientists to distinguish identity.