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1 .This is Scientific American 60-Second Science.I'm David Biello.Got a minute?
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2 .Chestnut trees once carpeted the eastern U.S.
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3 .Three billion of them fed and sheltered many forest residents, until the early decades of the 20th century when a fungal disease called chestnut blight killed almost every last one of the trees.
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4 .But now the American chestnut is making a comeback in its former range—thanks to genetic modification.
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5 .The blight came to the U.S.on imported Asian chestnuts, which are resistant to the disease.
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6 .With that resistance in mind, in the 1980's the American Chestnut Foundation began working to crossbreed the Asian chestnut with surviving individuals of its American cousin.
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7 .Such crossbreeding is time-consuming, however, and results in something less than a full American chestnut.
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8 .In a bid to speed up restoration work and minimize the need for genetic changes,
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9 .scientists at SUNY College of Environmental Science and Forestry have introduced genes into the American chestnut from wheat that help disarm the fungus.
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10 .And, in future, genes from its Chinese cousin, other trees and even grapes could help make the American chestnut even more resistant to the deadly blight.
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11 .A few of the hybrid chestnuts have been planted in the wild from New Jersey to Virginia.
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12 .And test plots of the genetically foritified trees have shown promising results.
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13 .Some environmentalists worry about genetically modified organisms.
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14 .But a bit of genetic tweaking, whether by crossbreeding or gene insertion, looks like the only way to restore the chestnut to its former glory.
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15 .Thanks for the minute, for Scientific American 60-Second Science. I'm David Biello.
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