Automated DNA sequencing:

Automated DNA sequencing is now general place which is based on the chain termination technique but using a fluorescent dye attached to an oligonucleotide primer instead of using radioactive labeling. A various fluorescent dye is attached to the primer for each of the four sequencing reactions but, follow incubation, all four combinations are electrophoresed and combined on one gel lane. An laser detection systems then distinguish the identity of every termination product as it elutes from the gel. The sequence in that the various fluorescent products elute from the gel gives the DNA sequence.

Modern automated DNA sequencing systems designed to generate over half a million bases of sequence per day use sequencing gels contained in multiple capillary tubes (rather than in a slab gel format). Loading and Preparation of the samples onto the capillary gels is carried out through robots and data analysis is also automated.