答案是很多疾病基因并没有表现出来，甚至从来都没有表现出来。

The answer is that all genes do not express themselves at all times and many never do.

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一旦我们开始注意基因触发自己的原因，我们也许就能够防止那些疾病基因触发。

Once we begin to pay attention to the reasons that a gene might express itself, we may be able to prevent that gene from releasing its code for illness.

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疾病基因的触发必然有它的原因，否则在疾病基因的触发之下没有人能够活下来。

There must be a reason why the body would call upon a gene to express itself. Otherwise, none of us would be able to survive the onslaught of genetic expression.

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Genetic scans for disease predictions, and we talked about one way you might do that using gene chips.

基因扫描技术可用于预测疾病,我们讨论的基因芯片技术是其中的一种

耶鲁公开课 - 生物医学工程探索课程节选

If we looked at all 30000, genes that were important in each individual how do you pick out which ones are important for a particular disease?

如果我们检查人体中,所有三万个至关重要的基因,要怎样从中找出,导致某种疾病的特定基因呢

耶鲁公开课 - 生物医学工程探索课程节选

Usually this is a disease that's caused by a defect in a single gene.

通常在疾病是由,单基因缺陷引起时才可行

耶鲁公开课 - 生物医学工程探索课程节选