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.

26.In 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

[C] fully use genetic information

[D] achieve the claimed accuracy

29. In the last paragraph ,a problem commercial genetic testing faces is __________.

[A]disorganized data collection

[B] overlapping database building

30. An appropriate title for the text is most likely to be__________.

[A]Fors and Againsts of DNA testing

[B] DNA testing and It’s problems

[C]DNA testing outside the lab

[D] lies behind DNA testing
 

Text 2

26.【A】推理判断题。 意为：从第一二段文章表明PTK很容易买到。

文中第一二段有多处体现，首段最后一句话“只需花30美元在地方药房作亲子鉴定……”.第二段第一句我们可以看到 “自从去年不需要处方即购可买之后，己经超过6万人购买了PTK ”。甚至从第二段整段我们可以看出：B项关于鉴定价格浮动只在第二段最后一句有所体现。C项文中未提到。D项属过度推断。

27.【C】事实细节题。 意为：PTK是用来鉴定亲子关系的。

从文中第三段可以看到“被收养的孩子可以通过亲子鉴定找到他具有血缘关系的亲属”。A选项比较具有迷惑性，从第三段后半句我们可以看出“PTK最近惹怒了很多谱系学家，他们支持用PTK来探寻一个家族的祖藉”。可以看出PTK没有主要被用来寻找一个人的出生地。选项B，D文中未提及。

28. 【D】事实细节题。意为：持怀疑态度的观察者认为祖先鉴定没有达到声称的准确性。

从题干信息我们可以将它定位到文中第五段第一句我们可以看出: 那些正在做祖先鉴定的人们所宣扬的(祖先鉴定)精确度其实是错的。这句话是对这一段的概括，ABC三个选项都只是它的细节之一。因此，D选项正确。

29.【A】事实细节题。意为：最后一段中商业基因鉴定面临的一个问题是数椐收集的紊乱。

从最后一段第二句我们可以看出“一些公司使用的数据库并不依赖于系统的数据收集而是把不同研究机构收集的信息合在一起。这就意味着处理数据的公司不同，所用DNA数据库也会不同。”文中并未提及数据是否重合，B无根椐。CD文中没有体现。

30.【B】主旨大意题。 意为：本文最合适的题目应是DNA测试及它存在的问题。

A选项中 “DNA测试的赞成与反对”从文中我们看不到作者有明显赞成DNA测试的倾向，C选项，文中没有特别强调实验室内外的问题。D选项“DNA测试背后的谎言”， 作者只是客观地提出了DNA测试存在的不准确性问题，但并没有指明是哪些人的谎言。