【英语时差8,16】向癌症进化

Evolving Toward Cancer Is it possible that humans evolved to get cancer? That’s what scientists at Ben Gurion University in Israel claim in a study. They found that the same genetic² mutations involved in the evolution of modern humans also gave rise to the evolution of cancer. But why would we have evolved to be at risk for diseases, like cancer, that make our survival more perilous³? Isn’t evolution about the survival of the fittest? Sort of. Because what it means to be “fittest” is complicated. Evolution basically describes how organisms–humans included–respond to environmental change. Thanks to random⁴ genetic mutations, some members of a group or species live to have babies and pass on their genes⁵. Others–those less fit–die off. After several generations, the mutations that enabled survival spread more broadly through the gene¹ pool. But those same mutations can have other, less desirable effects. Like giving rise to new diseases. And that’s what the Israeli researchers found when they looked at the record of mutations in the DNA⁶ of human mitochondria–tiny cellular⁷ engines necessary for a cell’s survival. Ancient mutations in mitochondrial DNA are the same as those found in the cells of many tumors. So it appears that those mutations that helped our prehistoric⁸ ancestors survive have a dark side–they’ve made us vulnerable to cancer and maybe other diseases. Now, the causes of cancer are complex. Genetic mutations are only one factor. But this research is important, the scientists say, because it strengthens the idea that cancer is linked to our genes. And knowing more about how diseases form and evolve can lead to new treatments and cures.

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 perilous   

adj.危险的，冒险的

参考例句：

• The journey through the jungle was perilous.穿过丛林的旅行充满了危险。
• We have been carried in safety through a perilous crisis.历经一连串危机，我们如今已安然无恙。

4 random   

adj.随机的；任意的；n.偶然的(或随便的)行动

参考例句：

• The list is arranged in a random order.名单排列不分先后。
• On random inspection the meat was found to be bad.经抽查，发现肉变质了。

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

6 DNA   

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

• DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。
• Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

7 cellular   

adj.移动的；细胞的，由细胞组成的

参考例句：

• She has a cellular telephone in her car.她的汽车里有一部无线通讯电话机。
• Many people use cellular materials as sensitive elements in hygrometers.很多人用蜂窝状的材料作为测量温度的传感元件。

8 prehistoric   

adj.（有记载的）历史以前的，史前的，古老的

参考例句：

• They have found prehistoric remains.他们发现了史前遗迹。
• It was rather like an exhibition of prehistoric electronic equipment.这儿倒像是在展览古老的电子设备。