Genetic analysis. Multi-pipette being used to add 12 samples of DNA to an electrophoresis gel tray. The DNA (deoxyribonucleic acid) has had a purple dye added. The electrophoretic gel has an electric field applied to it, and this causes the DNA samples to separate into their component parts to form a sequence of bands. This can then be used to obtain the order of the nucleotide groups along the DNA molecule (called sequencing the DNA). DNA is the genetic material that controls the growth and development of living organisms. Photographed at the Genethon Laboratory in France.