Chapter 18, Problem 23P

Geneticists are currently considering using technologies described in this chapter to de-extinct the woolly mammoth, a species that disappeared roughly 4000 years ago.

a.	Frozen specimens of woolly mammoths have been found in the Siberian tundra. If intact, living cells could be obtained from these samples, how could you attempt to bring back these long-extinct animals using these cells and oocytes from Asian elephants, a closely related species?
b.	Scientists have determined the genome sequence of the mammoth from frozen samples. These researchers are now trying to understand the adaptations that allowed these creatures to survive extreme cold. For example, mammoths had much thicker hair than do any elephants. How in theory could you use CRISPR/Cas9 to investigate the genetic basis of the difference in hair thickness between mammoths and elephants?
c.	How (again in theory) might it be possible to extend the CRISPR/Cas9 technique to de-extinct the mammoth? What kinds of technical challenges are involved in this approach? Why do you think some people consider the idea of de-extinction to be unethical?