DNA sequencing

This 3D animation shows you how scientists during the Human Genome Project read the letters in DNA, a process called DNA sequencing.

We start by seeing the DNA being chopped up and inserted into bacterial cells, which are then grown up. The DNA is then isolated and a mixture of DNA polymerase enzyme, primers, unlabelled DNA bases and fluorescently-labelled DNA bases are added. We then see the sequencing reaction take place and what happens to generate lots of pieces of DNA of different lengths. These pieces of DNA are then separated by length by a technique called electrophoresis and the DNA sequence ‘read’. Every step of the process is clearly shown in this animation!