Question

Recently, the power of cloning to rescue endangered or extinct species was demonstrated by applying nuclear transfer methods to save the mouflon, a species of wild sheep (left half of figure). This result piqued a fair amount of general interest, because of its possible implications for the return of other, more exotic, species from the jaws of extinction (as pictured on the right). Suppose a wealthy investor came to you with a proposal to create a real-life Jurassic Park (naturally, with far more detailed strategy to contain the animals), asking for your scientific analysis of their plan to use SCNT to bring back dinosaurs.

a. Considering all of the materials and technical steps involved in the process of nuclear transfer, list three problems you envision will be encountered by their team of scientists.

b. Speculate on how a researcher might overcome each of the obstacles you identified in (a), or state why you feel they may be insurmountable.

c. Given your analysis in (a) and (b), briefly comment on whether you think that the wealthy investor’s plan is feasible.

Answer 1

Somatic Cell Nuclear Transfer (SCNT) is a technique in which nucleus of a somatic cell is removed and transferred to the cytoplasm of an enucleated egg cell. This technique is useful in the process of Organisms cloning. This technique can also be used to save the species that are on the verge of extinction and if the DNA of an extinction specie is available it can also be used to bring back that extinct species in a process known as de-extinction.

a. Three problems in bringing back dinosaurs to setup a Jurassic park through SCNT are:

1. Finding intact DNA of dinosaurs.

2. Finding suitable ovum donor and the surrogate.
3. Lack of availability of genomic sequence of the extinct dinosaurs.

b.

1. Intact DNA can only be found if a fossil is well preserved along with the tissues e.g. Mammoths so finding intact or partial DNA can be insurmountable.

2. Suitable ovum for enucleation can be obtained from a related species like Crocodilians.

3. If Partial DNA is available then the left out regions of DNA can inserted into the genome by finding homologous with the DNA of a related species.

c. Wealthy investor’s plan is not feasible as preservation of soft tissues is very difficult and preservation of DNA inside a fossilised soft tissue is even more difficult. Other way to bring back dinosaurs is back breeding and the organisms that can be chosen for this purpose can be birds but it is a cumbersome process and not feasible.