Sequencing of Genomes - In recent years, considerable effort is being directed towards sequencing of whole genoms in a variety of microorganisms and eukaryotes. The largest genone sequenced completely so far belongs to cytomegalovirus (2, 00,000 base pairs).

The genome of E. coli (4'8 x 106bp) has also been sequenced to 76% level. The progress on sequencing of whole genome in a variety of organisms. It is expected that by the end of the present century, complete genomes of several organisms including that of human beings will be sequenced.