Sequencing technologies

How have gene sequencing technologies developed and what does this mean for researchers today?

The first complete genome to be sequenced, in 1977, came from a tiny bacterium-infecting virus called phi X174. It has just 11 genes, and a little over 5000 base pairs. Since then, biology has seen an explosion of sequence information. Small genomes can now be generated in hours or days.

The speed is a by-product of the efforts which went into the Human Genome Project. Ever-improving technologies have made DNA sequencing faster, more accurate, and far cheaper. In 1997, it cost about $1 per base to sequence DNA. A decade later, $1 paid for 1000 bases.

Today, DNA sequences are stored in fast-growing computer databases. The data centre at the Wellcome Trust Sanger Institute outside Cambridge currently has four petabytes (peta = 1 followed by 15 zeros) of storage, enough for around 15 000 laptops. Researchers need powerful software to search the DNA sequences. Bioinformatics - the art of harnessing computer power to make sense of mountains of biological data - is a growth area along with genomics.

Improvements in the rate of DNA sequencing over the past 30 years and into the future

From slab gels to capillary sequencing and second-generation sequencing technologies, there has been a more than a million-fold improvement in the rate of sequence generation over this time scale.

Graph reproduced with permission from Macmillan Publishers Ltd: Nature 458, 719-724 (2009).

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