Advances in DNA technology (Post Watson and Crick)

•DNA profiling•Genomic sequencing•Genetic engineering•Gene therapy

Techniques involved

•Cutting DNA•Separating pieces of DNA according to their size•Copying DNA•Sticking pieces of DNA together•DNA probes

How do you sequence a genome?1. First – Map the genome2. The shear it3. The place the fragments into BAC (bacterial

artificial chromosomes) then put the BACs into bacteria

4. Culture the bacteria until you have many of them

5. Harvest the DNA then separate out the different bits of DNA using gel electrophoresis

6. Sequence the bits of DNA 7. The sequences overlap, so use a computer

program to work out the order they go in

A G G C G A T T A G CA G C T T T G C A C T

C A C T A T T T G G A T C G A T C A T G C C A T G G

Questions….

1. A particular gene is found in all small pox viruses, but not in cow pox viruses. What would you conclude about this gene?

2. A particular gene is found, in a very similar form, in almost all living organisms, what would you conclude about this gene.

3. Suggest an example of a gene that might be found in all plants, but not animals.

Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

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Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

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Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

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Gel electrophoresisUsed to separate out pieces of DNA on the basis of their size

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http://plantandsoil.unl.edu/croptechnology2005/gen/animationOut.cgi?anim_name=Gel_electrophoresis.swf