Cloning DNA Fragments 



In vivo cloning. By propagating the fragments inside living cells. DNA pieces can be 

 immortalized, and the amount of specific DNA can be amplified (Fig. 7). Bacteria are 

 most often the hosts, but yeast and mammalian cells are also used. These cloning 

 procedures provide unlimited amounts of material for experimental study. 



Fig. 7. Cloning and libraries. A 



DNA fragment can be cloned in 

 bacteriophages or yeast artiticial 

 chromosomes (YACs). The 

 minimum number of separate 

 fragment clones needed in a library 

 to cover the human genome of 

 3x10^ bp is shown. 



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