Cloning by Genetic Methods,Phenotypes,Microbiological Techniques,Recombinant Vector,Foreign Gene

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	Cloning by Genetic Methods - Genetic methods involve using special characteristics or phenotypes coded by the gene present in the vector. This method becomes very efficient when combined with microbiological techniques. Plasmids and cosmids carry drug resistance or nutritional markers which help in the identification of the recombinant. This method is a prerequisite to differentiate the recombinant vector from non recombinant vector. Most researchers use blue-white selection or insertional inactivation of a drug resistance marker as the standard method of selection.
If an inserted foreign gene in the desired recombinant is expressed, then genetic selection may provide the simplest method for isolating clones containing the genes, For example, if a gene codes for enzymes which are important for metabolizing some toxin, then clones which carry the genes can be selected by transforming into bacteria which are susceptible to the toxin and then plating them on toxin containing plates. This method eliminates all other clones which do not have inserts, inserts which code for some other proteins and also the genes which are wrongly inserted.