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In brief : Golden genes

点击量:   时间:2017-06-05 02:01:01

CHEMISTS have found a new way to spot genetic mutations—using gold. When ground into spheres 13 nanometres across, electrons in the particles rush back and forth when illuminated, making a solution of them appear red. Change the spacing of the particles and you change the colour of the solution. Chad Mirkin and his colleagues at Northwestern University in Evanston, Illinois, attached gold particles to DNA segments. The segments initially appeared red, but when the team added complementary DNA, the gold-DNA bound to the new strands and clumped together, turning the solution purple. If there’s a mutation in the added DNA, giving an imperfect match,