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The inventor of a new machine that decodes DNA with semiconductors has used it to sequence the genome of Gordon Moore, co-founder of Intel, a leading chip maker.
The inventor, Jonathan Rothberg of Ion Torrent Systems (opens in new page, site includes videos via Technology tab) in Guilford, Conn., is one of several pursuing the goal of a $1,000 human genome, which he said he could reach by 2013 because his machine is rapidly being improved.
“Gordon Moore worked out all the tricks that gave us modern semiconductors, so he should be the first person to be sequenced on a semiconductor,” Dr. Rothberg said.
At $49,000, the new DNA decoding device is cheaper than its several rivals. Its promise rests on the potential of its novel technology to be improved faster than those of machines based on existing techniques.
Manufacturers are racing to bring DNA sequencing costs down to the point where a human genome can be decoded for $1,000, the sum at which enthusiasts say genome sequencing could become a routine part of medical practice.
But the sequencing of Dr. Moore’s genome also emphasizes how far technology has run ahead of the ability to interpret the information it generates.
Dr. Moore’s genome has a genetic variant that denotes a “56 percent chance of brown eyes,” one that indicates a “typical amount of freckling” and another that confers “moderately higher odds of smelling asparagus in one’s urine,” Dr. Rothberg and his colleagues reported Wednesday in the journal Nature. There are also two genetic variants in Dr. Moore’s genome said to be associated with “increased risk of mental retardation” — a risk evidently never realized. The clinical value of this genomic information would seem to be close to nil.
Dr. Rothberg said he agreed that few genes right now yield useful genetic information and that it will be a 10- to 15-year quest to really understand the human genome. For the moment his machine is specialized for analyzing much smaller amounts of information, like the handful of genes highly active in cancer.
The Ion Torrent machine requires only two hours to sequence DNA, although sample preparation takes longer. The first two genomes of the deadly E. coli bacteria that swept Europe in the spring were decoded on the company’s machines.
The earliest DNA sequencing method depended on radioactivity to mark the four different units that make up genetic material, but as the system was mechanized, engineers switched to fluorescent chemicals. The new device is the first commercial system to decode DNA directly on a semiconductor chip and to work by detecting a voltage change, rather than light.
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