It is a wise father that knows his own child, but today a man can boost his paternal(fatherly)wisdom — or at least confirm that

admin2016-01-10  33

问题     It is a wise father that knows his own child, but today a man can boost his paternal(fatherly)wisdom — or at least confirm that he’ s the kid’ s dad. All he needs to do is to shell out $30 for paternity testing kit(PTK)at his local drugstore — and another $120 to get the results.
    More than 60 000 people have purchased the PTKs since they first become available without prescriptions last year, according to Doug Fogg, chief operating officer of Identigene, which makes the over-the-counter(无需处方的)kits. More than two dozen companies sell DNA tests directly to the public, ranging in price from a few hundred dollars to more than $2 500.
    Among the most popular; paternity and kinship(亲属关系)testing, which adopted children can use to find their biological relatives and families can use to track down kids put up for adoption. DNA testing is also the latest rage among passionate genealogists(系谱学者)— and supports businesses that offer to search for a family’ s geographic roots.
    Most tests require collecting cells by swabbing saliva(唾液)in the mouth and sending it to the company for testing. All tests require a potential candidate with whom to compare DNA.
    But some observers are skeptical. "There’ s a kind of false precision being hawked by people claiming they are doing ancestry testing," says Troy Duster, a New York University sociologist. He notes that each individual has many ancestors — numbering in the hundreds just a few centuries back.
    Yet most ancestry testing only considers a single lineage, either the Y chromosome(染色体)inherited through men in a father’ s line or mitochondrial(线粒体的)DNA, which is passed down only from mothers. This DNA can reveal genetic information about only one or two ancestors, even though, for example, just three generations back people also have six other great-grandparents or, four generations back, 14 other great-great-grandparents.
    Critics also argue that commercial genetic testing is only as good as the reference collections to which a sample is compared. Databases used by some companies don ’ t rely on data collected systematically but rather lump together information from different research projects. This means that a DNA database may have a lot of data from some regions and not others, so a person’ s test results may differ depending on the company that processes the results. In addition, the computer programs a company uses to estimate relationships may be patented and not subject to peer review or outside evaluation.
Skeptical observers believe that ancestry testing fails to______.

选项 A、trace distant ancestors
B、rebuild reliable bloodlines
C、fully use genetic information
D、achieve the claimed accuracy

答案D

解析 细节题。根据题干中的skeptical observers定位到第五段。作者引用社会学家TroyDuster的话说明评论家为何对基因测试持有怀疑态度:There is a kind of false precision beinghawked by people claiming they are doing ancestry testing(那些宣称做血统测试的人夸大了测试的准确性),false对应题干中的fails to,precision对应D项中的accuracy,故D项为正确答案。
转载请注明原文地址:https://kaotiyun.com/show/7ysZ777K
0

最新回复(0)