09年研究生考试英语阅读真题分篇 text-2

2021年1月16日发(作者：戴思颜)
2009全国硕士研究生入学考试英语试题
Text 2
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 shell our $$30 for paternity testing kit (PTK) at his local
drugstore – and another $$120 to get the results.
More than 60,000 people have purchased the PTKs since they first become available without prescriptions
last years, according to Doug Fog, chief operating officer of Identigene, which makes the over-the-counter kits.
More than two dozen companies sell DNA tests Directly to the public , ranging in price from a few hundred
dollars to more than $$2500.
Among the most popular : paternity and kinship testing , which adopted children can use to find their
biological relatives and latest rage a many passionate genealogists-and supports businesses that offer to search for
a family’s geographic roots .
Most tests require collecting cells by webbing saliva 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 is a kind of false precision being hawked by people claiming they
are doing ancestry testing,” says Trey 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 inherited through men in a father’s line or mitochondrial
DNA, which a 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 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.
paragraphs 1 and 2 , the text shows PTK’s ___________.
[A]easy availability
[B]flexibility in pricing
[C] successful promotion
[D] popularity with households
27. PTK is used to __________.
[A]locate one’s birth place
[B]promote genetic research
[C] identify parent-child kinship
[D] choose children for adoption
28. Skeptical observers believe that ancestry testing fails to__________.
[A]trace distant ancestors
[B] rebuild reliable bloodlines