文字稿

科学家说他们现在已经对引起乳腺癌的几乎全部基因突变有了近乎完美的认识。这项发表在《自然》期刊上的研究结果被称为具有“里程碑”意义的时刻，因为此研究结果可以帮助解锁治疗乳腺癌和防止乳腺癌发病的新手段。以下是 James Gallagher 的报道。

To understand the causes of cancer, scientists have to know what goes wrong in our DNA – our blueprint of life – that transforms healthy tissue into cancerous tissue. Scientists, led by the Sanger Institute in Cambridge, analysed all 3 billion letters of the genetic code in more than five hundred patients with breast cancer in the largest ever study of its kind.

The researchers say there are ninety three sets of instructions or genes that if mutated can cause tumours. Professor Sir Mike Stratton, the Director of The Sanger Institute, said understanding had been transformed. He believes new drugs could eventually be targeted at each of the mutations, similar to the way Herceptin is already being used.

The scientists also tried to find out why genes become mutated in the first place.

Mutations leave scars on our DNA and that allowed the team to identify twelve types of damage that cause mutations in breast tissue. Some are related to family risk, others seem to be the result of fighting off infections but most are still unexplained. But understanding those, offers hopes at being able to prevent some cancers in the first place.

词汇表

blueprint 蓝图
transforms 转变，使变样
analysed 分析，研究
genetic code 遗传密码
genes 基因
mutated （遗传物质）突变了，变异了
tumours 肿瘤
transformed 被转变了
targeted 被定向的，使针对的
scars 伤痕，伤疤
infections 感染

测验

请听报道并回答下列问题。

1. Did all the patients involved with this research have breast cancer?

2. True or false? Tumours can be caused by a change in our genes.

3. What did scientists find was the most common reason for scars on our DNA that caused mutations in breast tissue?

4. How many letters in the genetic code of the patients did scientists look at?

答案

1. Did all the patients involved with this research have breast cancer?
Yes. 3 billion letters of the genetic code in more than five hundred patients with breast cancer were analysed.

2. True or false? Tumours can be caused by a change in our genes.
True. Researchers say there are ninety three sets of instructions or genes that if changed in some way - or mutated - can cause tumours.

3. What did scientists find was the most common reason for scars on our DNA that caused mutations in breast tissue?
They're not sure - most are still unexplained.

4. How many letters in the genetic code of the patients did scientists look at?
They analysed all 3 billion letters of the genetic code.