Unit 19 Cloning
Do
you agree or dis-agree with the following statements? Why?
People will some- day be cloned for spare parts.
Cloning is a dan- gerous technology that should beillegal.
The cloning of endangered animals will some- day be an importantscience.
If my pet died, I would want to clonehim.
When I die, I want to becloned.
Read and translate the text aboutcloning.
Cloning and concerns about it
Cloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in bio- technology refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell clon- ing), or organisms.
Molecular cloning refers to the process of mak- ing multiple molecules. It is used in a wide array of
biological experiments and practical applications rang- ing from genetic fingerprinting to large scale protein production.
Cloning of any DNA fragment essentially in- volves four steps. First is fragmentation - breaking apart a strand of DNA; second is ligation - gluing to- gether pieces of DNA in a desired sequence; third is transfection - inserting the newly formed pieces of DNA into cells and the last is screening or selection - selecting out the cells that were successfully trans- fected with the new DNA. Cloning a cell means to de- rive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multicellu- lar organisms, cell cloning is an arduous task as these cells will not readily grow in standard media.
Organism cloning (also called reproductive clon- ing) refers to the procedure of creating a new multicel- lular organism, genetically identical to another. In es- sence this form of cloning is an asexual method of re- production, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a natu- rally occurring phenomenon in many species, includ- ing most plants (vegetative reproduction) and some insects. Scientists have made some major achieve- ments with cloning, including the asexual reproduc- tion of sheep and cows.
There is a lot of ethical debate over whether or not cloning should be used. However, in the United
States, the human consumption of meat and other products from cloned animals was approved by the FDA (The Food and Drug Administration) on Decem- ber 28, 2006, with no special labeling required. Cloned beef and other products have since been regu- larly consumed in the US withoutdistinction.
Because of recent technological advancements, the cloning of animals (and potentially humans) has been an issue. The Catholic Church and many reli- gious organizations oppose all forms of cloning, on the grounds that life begins at conception. They con- cern about the protection of the identity of theindivid-
asexualreproduction biological blueprint break apart (v) concern consumption counterpart
derive (v) fertilization fragment (v) fragmentation