The process of changing the genetic structure of food crops has been debated for some time.

这种改变粮食作物基因结构的过程已经进行了一段时间的辩论。

But the same study finds that Americans do not support changing the genetic structure, or DNA, of children so that they are faster, taller or more intelligent.

而这项调查还发现，美国人不支持改变儿童的遗传结构（DNA），让他们变得更敏捷、更高大或者更聪明。

They compared the genetic structure of polar bears with that of their closest relatives from a warmer climate, the brown bears.

他们将北极熊的基因结构与来自温暖气候的近亲棕熊的基因结构进行了比较。