Then, using gene-location data from the Human Genome Project, they can see which nearby genes are likely, if they malfunction, to lead to the disease.

ECONOMIST: Human genetics

There are two ways that knowing a gene's location can make companies like Myriad money.

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Again, scientists know the genetic area to search, but they do not know the gene's precise location.

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In 1983 researchers found the approximate location of the gene for Huntington's disease, the incurable brain illness.

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Mehrabian painstakingly analyzed the genomes of 500 mice and, by 2001, had found the rough location of a gene that seemed to prevent atherosclerosis.

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Could a strand of DNA be spliced open at a precise location at the beginning of a gene?

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