读者文摘:我认为我是无辜的(2)

Back in the 1980s, when DNA¹ forensic² analysis was new, crime labs needed a speck³ of bodily fluid—usually blood, semen, or spit—to generate a genetic⁴ profile.

在20世纪80年代，DNA法医分析还是一项新技术，犯罪实验室需要一点身体的液体——通常是血液、精液或唾液——来生成基因图谱。

But in 1997, Australian scientist Roland van Oorschot stunned⁵ the criminal-justice world with the discovery that some people's DNA appeared on things that they had never touched.

但是在1997年，澳大利亚科学家罗兰·范·奥尔斯科特发现，一些人的DNA会出现在他们从未接触过的东西上，这一发现震惊了刑事司法领域。

He called the phenomenon "secondary transfer." One of his lab's experiments had three people sit at a table and share a jug⁶ of juice.

他称这种现象为“二次转移”。他在实验室做的实验之一是，让三个人坐在桌子边，共享一罐果汁。

After 20 minutes, their hands and the chairs, juice glasses, table, and jug were swabbed and tested for genetic material.

20分钟后，他们的手、椅子、果汁杯、桌子和水壶都被擦洗，并进行了遗传物质测试。

Although the volunteers never touched one another, their DNA ended up on each other's glasses—and hands.

尽管这几位志愿者从未碰过彼此，但是他们的DNA出现在彼此的杯子上和手上。

Then there was the foreign DNA—profiles that didn't match any of the juice drinkers.

然后出现了其他DNA，其特征不符合任何一位志愿者的DNA。

It turned up on about half of the chairs and glasses and all over the participants' hands and the table.

它出现在一半的椅子和杯子上。也出现在桌子上和所有志愿者的手上。

The only explanation: The participants had unwittingly brought with them alien genes⁷,

唯一的解释是：这些参与者不经意地携带了外源基因，

perhaps from the lover they had kissed that morning, the stranger with whom they had shared a bus grip, or the barista who had handed them an afternoon latte.

也许是来自他们那天早上亲吻的爱人，或是和他们握一个公交车把手的陌生人，或者是下午递给他们一杯拿铁咖啡的咖啡师。

In a sense, this isn't surprising: We leave a trail of ourselves everywhere we go. One person can shed upward of 50 million skin cells a day.

在某种意义上来说，这并不令人惊讶：无论我们走到哪里，都会留下自己的足迹。一个人每天可以脱落超过5000万个皮肤细胞。

We also spew saliva⁸. If we stand still and talk for 30 seconds, our DNA may be found more than a yard away. DNA is the most accurate forensic science we have.

我们也吐唾液。如果我们站着说话30秒钟，我们的DNA可能在一码之外找到。DNA分析是我们拥有的最精准的法医学技术。

It has exonerated⁹ scores of people who had been convicted using more flawed disciplines, such as hair or bite-mark analysis.

它为数十名曾因使用头发或咬痕分析等更有缺陷的分析而被定罪的人洗脱了罪名。

Meanwhile, there have been few publicized cases of DNA mistakenly implicating¹⁰ someone in a crime.

与此同时，很少有公开的因DNA错误而使某人卷入犯罪的案例。

Nevertheless, the itinerant¹¹ nature of DNA has serious implications for forensic investigations¹².

不过，DNA的流动性质对法医调查有着严重的影响。

After all, if traces of our DNA can make their way to a crime scene we've never visited, aren't we all possible suspects?

毕竟，如果我们的DNA出现在我们从没参观过的犯罪现场，我们不就都成了嫌疑犯了吗？

1 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。

2 forensic   

adj.法庭的，雄辩的

参考例句：

• The report included his interpretation of the forensic evidence.该报告包括他对法庭证据的诠释。
• The judge concluded the proceeding on 10:30 Am after one hour of forensic debate.经过近一个小时的法庭辩论后，法官于10时30分宣布休庭。

3 speck   

n.微粒，小污点，小斑点

参考例句：

• I have not a speck of interest in it.我对它没有任何兴趣。
• The sky is clear and bright without a speck of cloud.天空晴朗，一星星云彩也没有。

4 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。

5 stunned   

adj. 震惊的，惊讶的 动词stun的过去式和过去分词

参考例句：

• The fall stunned me for a moment. 那一下摔得我昏迷了片刻。
• The leaders of the Kopper Company were then stunned speechless. 科伯公司的领导们当时被惊得目瞪口呆。

6 jug   

n.(有柄，小口，可盛水等的)大壶，罐，盂

参考例句：

• He walked along with a jug poised on his head.他头上顶着一个水罐，保持着平衡往前走。
• She filled the jug with fresh water.她将水壶注满了清水。

7 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

8 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

9 exonerated   

v.使免罪，免除( exonerate的过去式和过去分词 )

参考例句：

• The police report exonerated Lewis from all charges of corruption. 警方的报告免除了对刘易斯贪污的所有指控。
• An investigation exonerated the school from any blame. 一项调查证明该学校没有任何过失。 来自辞典例句

10 implicating   

vt.牵涉，涉及（implicate的现在分词形式）

参考例句：

• He was in the public dock, confessing everything, implicating everybody. 他站在被告席上，什么都招认，什么人都咬。 来自英汉文学
• No one would have had me get out of the scrape by implicating an old friend. 无论什么人都不能叫我为了自己摆脱困难便把一个老朋友牵累到这案子里去。 来自辞典例句

11 itinerant   

adj.巡回的；流动的

参考例句：

• He is starting itinerant performance all over the world.他正在世界各地巡回演出。
• There is a general debate nowadays about the problem of itinerant workers.目前，针对流动工人的问题展开了普遍的争论。

12 investigations   

（正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究

参考例句：

• His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查，但没有发现什么。
• He often sent them out to make investigations. 他常常派他们出去作调查。