The price of sequencing a human genome is about to plummet. A company called Complete Genomics, based in Mountain View, California, says it can read entire human genomes at $5000 a shot.
When James Watson – co-discoverer of the DNA double-helix – became the first individual to have his genome sequenced, in 2007, the cost was around $1 million. But several companies are now working on advanced technologies to allow faster and cheaper sequencing.
Last year, for instance, Applied Biosystems of Foster City, California, announced that it had sequenced the genome of a Nigerian man for less than $60,000.
Complete Genomics says it can beat that cost by more than a factor of 10, and it is putting its business plan where its mouth is: companies and academic researchers will be able to start placing orders at the quoted $5000 price tag from June this year.
Try before you buy
When New Scientist interviewed Watson in 2007, he predicted a revolution in understanding human genetic variation once reading each person's genome "gets down to the cost of a Chevrolet".
Complete Genomics' sequences will be cheaper than many second-hand cars, and prospective customers can now kick the tyres of the company's product – CG's first human genome sequence has been released on its website.
The initial genome sequence, announced on 5 February at the Advances in Genome Biology and Technology meeting on Marco Island, Florida, is from a blood sample collected in 1980 from a 63-year-old man from Utah. "This is as good a quality genome as has ever been produced," claims Clifford Reid, the company's president. There is scope for improvement, however, as meeting attendees have noted that the technology has problems dealing with repetitive DNA sequences.
The company's technology relies on immobilising amplified fragments of DNA on a high-density silicon array, so that the fragments' sequences can be read quickly and efficiently. To do this, circles of DNA about 230 bases long are copied multiple times to form "nanoballs" that stick to the array.
Price no barrier
The first customers are likely to be academic researchers interested in uncovering the genetic roots of complex conditions such as cardiovascular disease, and drug firms that want to understand how genetic variation affects people's responses to their products.
But as prices continue to come down, the technology could also be attractive to companies that are already offering more limited genome scans to members of the public. Such companies are currently studying up to a million single-letter variants in the genetic code known as single nucleotide polymorphisms.
Sean George, chief operating officer of Navigenics in Redwood Shores, California, expects his company to start offering genome sequencing to its customers by early next year – although no decision has yet been taken about which technology they will use.
So far, personal genome sequencing has been the preserve of the super-rich. Knome of Cambridge, Massachusetts, today offers the service for $99,500, through a contract with a team at the Beijing Genomics Institute in China.
X-Prize potential
One of Knome's founders is George Church, a specialist in sequencing technology at the Harvard Medical School in Boston, who is also an adviser to Complete Genomics. Discussions are underway between the two firms.
Still, Knome president Jorge Conde warns that the price to its customers will remain higher than the basic cost of sequencing a genome, as much of the value comes from the expert analysis needed to interpret the sequence. "The average person cannot speak the language of As, Cs, Gs, and Ts," he says.
If Complete Genomics delivers as promised, the company could also be eligible for the Archon X Prize for Genomics, which will give $10 million for the first team to sequence 100 human genomes in less than 10 days for less than $10,000 each.
Complete Genomics has not yet entered the competition, however, as it intends to concentrate on fulfilling commercial orders. The company aims to sequence up to 1000 human genomes in 2009, and 20,000 in 2010.
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