Scientists ID someone from a single strand of hair

题材文章词数科技363 难度 ★★★体裁建议用时说明文7 min

难词探意

1. protein /ɪprəʊtiːn/ n. 蛋白质

2. follicle /ɪfɒlɪkl/ n. (皮肤上的)毛囊

3. detergent /dɪɪtзːdʒənt/ n. 洗涤剂

4.expertise/'ekspзːɪtiːz/n. 专业技能；专业知识

5. forensic /fəɪrenzɪk/ adj. 法医的

6. discrimination /dɪ'skrɪmɪɪneɪʃn/ n. 辨别力

A new technique could have criminals tearing their hair out： Researchers have developed a method from as little as 1 centimeter of hair—and that is eight times more sensitive than similarproteinanalysis techniques. If the new method ever makes it into the courtroom， it could greatly expand the ability to recognize the people at the scene of a crime.

To get reliable data from hair， scientists previously needed DNA from skin still attached to hairfollicles. But recent technologies have instead analyzed proteins in the hair itself， which can be used to recognize people with a high degree of accuracy without DNA.

To get more proteins for analysis， scientists developed a method with only one step： heating the hair indetergentsolution. They also identified a dozen new protein building blocks called genetically variant peptides (GVPs) that differ among individuals. “The more GVPs you have，the more people you can distinguish from each other，” says NIST health specialist and study author Zheng Zhang.GPVs aren't yet used to recognize people in criminal cases—but could be in the future， Zhang says.Protein sequences are highly individual， but there's still a chance—one in 1 million or even one in 10 million—that two people share the same one.

Admittedly， the new method has its drawbacks， says Glendon Parker， a biochemist at the University of California. Chief among them is the amount of time andexpertiseneeded. To get enough material to build a profile， scientists need 1 day or more， Parker says. The time-consuming new technique might be the best choice for discovering new GVPs， he says， but other techniques with lower skills may be better for use.

In addition， no identification method based on GVPs has been used in court. There are still a lot of questions to be answered before that's a reality， says Monte Miller， aforensicexpert who has testified in many cases involving DNA evidence.

“These answers are likely a long way off， but the research is interesting and it's useful，” Miller says. “Anything that gives us morediscriminationand more information is always good.” Until then，we'll be splitting hairs.

Reading Check

1. What's the breakthrough of the new technique in the text?

A. It collects reliable data from skin.

B. It makes progress in recognizing criminals.

C. It protects the remaining protein of the hair.

D. It's more accurate in finding evidence through DNA.

2. What are the disadvantages of the new method?

A. It can only be used in youth.

B. It requires time and expert skills.

C. It will cause a lot of debates.

D. Its techniques are less advanced than those of other methods.

3. Where is this text most likely from?

A. A diary. B. A guidebook. C. A novel. D. A magazine.

Language Study

Sentence for writing

The more GVPs you have， the more people you can distinguish from each other.

【信息提取】本句中，the more...， the more...为固定句型，前后的两个“more”不是一成不变的，都可以在具体的句子中换成相应的形容词比较级形式，主句是后面的“the more...”。需要注意的是两个“the more”后面加的是正常语序的句子。

【句式仿写】天越冷，你在街上看到的人越少。