Although the capture and trading of great apes has been banned...

Question

Although the capture and trading of great apes has been banned in 112 countries since 1973, it is estimated that about 1000 chimpanzees are removed annually from Africa and smuggled into Europe, the United States, and Japan. This illegal trade is often disguised by simulating births in captivity. Until recently, genetic identity tests to uncover these illegal activities were not used because of the lack of highly polymorphic markers (markers that vary from one individual to the next) and the difficulties of obtaining chimpanzee blood samples. A study was reported in which DNA samples were extracted from freshly plucked chimpanzee hair roots and used as templates for PCR. The primers used in these studies flank highly polymorphic sites in human DNA that result from variable numbers of tandem nucleotide repeats. Several offspring and their putative parents were tested to determine whether the offspring were 'legitimate' or the product of illegal trading. The data are shown in the following Southern blot.

Examine the data carefully and choose the best conclusion.
a. None of the offspring is legitimate.
b. Offspring B and C are not the products of these parents and were probably purchased on the illegal market. The data are consistent with offspring A being legitimate.
c. Offspring A and B are products of the parents shown, but C is not and was therefore probably purchased on the illegal market.
d. There are not enough data to draw any conclusions. Additional polymorphic sites should be examined.
e. No conclusion can be drawn because 'human' primers were used.

Southern blot showing DNA band patterns of chimpanzee parents and three offspring for genetic identity testing.

Examine the data carefully and choose the best conclusion.

a. None of the offspring is legitimate.

b. Offspring B and C are not the products of these parents and were probably purchased on the illegal market. The data are consistent with offspring A being legitimate.

c. Offspring A and B are products of the parents shown, but C is not and was therefore probably purchased on the illegal market.

d. There are not enough data to draw any conclusions. Additional polymorphic sites should be examined.

e. No conclusion can be drawn because 'human' primers were used.

Accepted Answer

Hi, everybody. Let's take a look at this practice problem together which of the following techniques is used to detect D N A sequences. Our answer choices are a northern blotting. Be southern blotting. See western blotting or D. Both A and B recall what blotting is since that is in all of our answer choices. Now, blotting is the process of detecting and separating out macro molecules and that can be D N A R N A or proteins. So the first step is to extract your sample or your macro molecule of interest. Your second step is to do electrophoresis and this separates out the macro molecule of interest. And then finally, you get blotting of your macro molecule onto a membrane. So you transfer that onto a membrane. Now recall that a northern blotting is a technique done to detect R N A. Therefore A is not the correct answer. And that means G which was both A and B is also not a correct answer. C western blotting is done to detect proteins. Therefore, C is also incorrect. Our correct answer therefore is option B southern blotting. Southern blotting is the technique used to detect D N A. All right. Everybody. I hope you found this helpful and I'll see you soon for the next practice problem.

Key Concepts

Variable Number Tandem Repeats (VNTRs)

Polymerase Chain Reaction (PCR) and Primer Specificity

Parentage Testing Using Genetic Markers

Watch next