In Britain, those who live to be 100 years old receive a birthday card from the queen. In the future, centenarians everywhere ma

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问题     In Britain, those who live to be 100 years old receive a birthday card from the queen. In the future, centenarians everywhere may also receive a call from a geneticist. If they do, he or she will be seeking a sample of DNA that might, eventually, help to reveal the genetic components of extreme longevity. The more immediate use, however, will be in a competition. For on October 26th the X Prize Foundation, based in Playa Vista, California, unveiled its latest carrot to the world’s scientists.
    The foundation has already put up prizes in areas as diverse as cleaning up oil spills and landing a robot on the moon. The idea of a genomics X prize is not new. It has been around since 2006. But the latest announcement, in the pages of Nature Genetics, has a particular goal in mind.
    The foundation is offering $10m to the first team to sequence the genomes of 100 centenarians. The winners will have to do it accurately, making no more than one mistake per million base pairs (the chemical letters in which genomic information is encoded). They will have to do it cheaply, spending less than $1,000 per genome. And they will have to do it quickly, within 30 days of starting.
    The goal of the project is twofold. First, to discover what, genetically speaking, makes centenarians different from other people. And second, to try to establish an industry standard for sequencing. This is something the field sorely needs. The cost of sequencing has plummeted over the past decade, and several technologies have emerged, each backed by different firms which will, for a suitable consideration, happily sequence your genome. No two firms, however, are likely to produce the same result. The full genome has 6 billion base pairs (3 billion from each parent, though many are duplicates), which means even the prize winner will be allowed 6,000 mistakes. And some parts, particularly those where the same short pattern of base pairs is repeated over and over again, remain difficult to sequence well. Moreover, several techniques are inherently unreliable, having traded speed and simplicity for accuracy.
    The new X prize is designed to winnow the genetic wheat from the chaff. The scientific standards for victory have been set by a team led by Larry Kedes. Dr. Kedes, who founded the Institute for Genetic Medicine at the University of Southern California, is the foundation’s main adviser on matters genomic. Besides the low error rate, Dr. Kedes requires that the sequence be complete-meaning that it includes at least 98% of the genome’s base pairs. That is taxing because some parts of a chromosome, such as those near the centromere (the place where the two arms of a chromosome meet) are not easy to get at. He also requires that it be sorted by haplotype. A haplotype is a group of genes that tend to travel through the generations as a block. Dr. Kedes wants it to be clear which haplotypes came from which parent.
    The contest will begin in January 2013 and last 30 days. The first team to score their century of genomes — at the new standards, price and speed — will win the prize. But the wider prize, an understanding of how to stay healthy into a ripe old age, with all that may bring to medical science, will ultimately be shared by everybody.
According to the first paragraph, we know centenarians will probably

选项 A、receive a birthday card from the British queen.
B、be called to donate a sample of their DNA for study.
C、be asked to reveal the secret of their longevity.
D、participate in a competition to win big money.

答案B

解析 事实细节题。根据文章首句,“英国的”百岁老人会收到女王寄出的生日贺卡,[A]以偏概全。第二、三句谈到,将来遗传学家可能会给百岁老人打电话,目的是寻找DNA样本,以便求得长寿的基因秘密,因此百岁老人可能会被要求捐献DNA样本以供研究用,[B]为答案。百岁老人可能会捐赠.DNA样本以便遗传学家研究他们长寿的秘诀,而不是他们自己解开长寿的秘诀,排除[C]。根据文章内容,不是百岁老人参加竞赛,而是the world’s scientists,排除[D]。
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