【英语时差8,16】为什么禁止近亲结婚？（下）

Similarly, if you mix two animals that have close genetic² makeups³, the offspring won’t be as healthy as the offspring of two genetically⁴ dissimilar parents. That’s because many diseases are caused by mutant genes⁵. If you inherit a mutant gene¹ from your mother, you can use the non-mutant version inherited from your father as a backup. If both mother and father had mutant versions of the gene, however, disease will result. Inbreeding makes it much more likely that two mutant copies of a gene will show up. So you can see the problem with endangered species. With fewer than about five hundred members, the gene pool is too restricted. Inbreeding is more likely. The following generations become progressively less healthy, eventually dying out.

1 gene   

n.遗传因子，基因

参考例句：

• A single gene may have many effects.单一基因可能具有很多种效应。
• The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。

2 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

3 makeups   

n.天性( makeup的名词复数 )；性格；气质；组成成分

参考例句：

4 genetically   

adv.遗传上

参考例句：

• All the bees in the colony are genetically related. 同一群体的蜜蜂都有亲缘关系。
• Genetically modified foods have already arrived on American dinner tables. 经基因改造加工过的食物已端上了美国人的餐桌。 来自英汉非文学 - 生命科学 - 基因与食物

5 genes   

n.基因( gene的名词复数 )

参考例句：

• You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因，所以能够活得很长。 来自《简明英汉词典》
• Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪