Passage Three: Questions 44-50 The mapping of the human genome, completed in 2003, cost $2.7 billion. Now the cost for an individual's whole-genome sequencing (WGS) is $7,500 and falling fast. One day WGS could be easy to get as a pregnancy test at the drugstore. In an ideal world, genetic analysis could save money by catching disease early, offering targeted treatments and measures. Dr. Katrina Armstrong, a professor at the University of Pennsylvania School of Medicine, notes that testing 21 genes could reveal which breast-cancer patients are unlikely to benefit from a particular chemotherapy —knowledge that could spare women the treatment and save $400 million each year. But a majority of doctors in a recent survey predicted that more testing will trigger higher costs, as patients with ambiguous results begin to seek frequent screenings—and potentially unnecessary procedures—for diseases they might never develop. Some genetic testing has already moved out of the lab and into the living room. Companies like 23andMe offer DNA analysis directly to consumers—no doctor required. Since 23andMe's founding in 2006, more than 180,000 people have been tested as the price has fallen from $999 for information on 14 specific traits and health risks to $99 for more than 200. The promise boils down to “forewarned is forearmed.” If parents learn that their child carries a gene called ApoE4, indicating a higher risk of Alzheimer's，they might discourage the child from playing youth hockey or football，since research has linked traumatic brain injuries with a greater likelihood of brain disease in people who test positive for ApoE4. But having more detailed genetic information does not always point to a clear path. Dr. Ian Krantz and Nancy Spinner, a husband-and-wife team at the Children's Hospital of Philadelphia, are working with an $8.8 million federal grant to understand what genomic information patients and parents want to know. Most parents go in looking for the cause of a mysterious illness. If you want to start an argument, ask doctors and patients what they think doctors should do when they discover genetic results they weren't looking for. It can be an emotional blow—and a lifelong burden—if a mom learns that her baby girl carries a mutation that increases her risk of ovarian cancer or a dad finds out that his aspiring linebacker is genetically predisposed to developing Alzheimer's. In focus groups that are part of Krantz and Spinner's study, nearly all the parents said they would want to know about every disease risk, even if there's no treatment available. But in groups of bioethicists, lab directors, geneticists, pediatricians and genetic counselors, the majority said only results that could be immediately acted on should be shared with families. Genome sequencing isn't the first medical development that has forced doctors to grapple with the question of how much to tell patients. There have been cases of physicians' choosing to keep quiet when a test revealed a child's father was not his or her biological father. In years past，doctors have agreed not to share news of a terminal illness with an elderly patient if the consensus was that the knowledge would cause too much anxiety. But perhaps nowhere is the risk of overreacting to murky results greater than in the field of prenatal testing. “Great, we can sequence the genome of a fetus. What the hell does it tell us?” says bioethicist Tom Murray, a visiting scholar at Yale. “Much less than most people probably believe. Probabilities are not the same as guarantees.” Faced with a growing need for protocols，the medical community is trying to hammer out some guidelines. The challenge doctors face in determining how much to tell patients—or their parents—is complicated by a steady stream of new discoveries. Test results that are indecipherable today could be lifesaving in 2025. But waiting years to share sequencing information is a logistical nightmare, particularly considering that patients may not remain under that geneticist's care and may change addresses many times over. Genomic transcripts are also so massive—labs typically FedEx a hard drive because there's too much data a transmit digitally that the information is often relegated to a hospital's archives, if it's saved at all. One possible solution to the problem of what to do with the deluge of data is a new Web-based venture called My46. Named for the number of chromosomes in human DNA，the nonprofit will allow people to store their sequencing results online and choose what they want to know and when. “Right now，it's not unusual for researchers to say that they're not returning the results because there's no good way to do it, says Dr. Michael Bamshad, chief of pediatric genetics at the University of Washington, who works with Burke and is helping develop My46, Eventually, he predicts, “everyone will have their genome stored in a cloud.” 【題組】44. What is the passage mainly about?
(A) The general public may benefit from the mapping of the human genome.
(B) Scientists are reluctant to do genetic analysis for the purpose of discovering the development of mysterious illnesses.
(C) Doctors are caught in an ethical dilemma about how much genomic information they should
reveal to the patients.
(D) Genome sequencing may help locate the cause of some mysterious disease.
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