h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

Does anyone know any information about the history and current developments of cloning, or how Dolly the sheep was cloned?
Im doing some research for a friend with Glandular Fever at the moment and can't think of a better place to find things out than here

Well lets see, it rather depends on what you mean by cloning but I'll have a go.

Back in the 19th century the transfer of genetic information was proposed.

In the early 20th century, nucleic acids (DNA and RNA) was discovered.

In the early 60s Watson and Crick elucidated the structure of DNA.

In the late 60s, the gentetic code was decoded - DNA bases, three at a time code for amino acid sequences in proteins.

In the very late 60s/early 70s restriction enzymes and DNA ligases were discovered. These allowed DNA to be chopped up and put back to together again at specific sites to be done. Along with the development of DNA sequencing this allowed specific genes to isolated and identified and then one could stick them in a foreign organism (Alost always E. coli) and use that organism to make the protein target of that gene.

This latter process is the most usual form of 'cloning' used in science. It enables us to isolate proteins that would otherwise be available in too small or a quantity for study. We can then look at their structure and function in detail.
TEchnically a clone is a colony of genetically identical organisms I believe. So the colony is the clone and not an indvidual.

In the mid 1980s the polymerase chain reaction (PCR) was discovered and used to speed up this process by orders of magnitude.

In terms of DOlly the sheep, that's out of my realm of knowledge a little but I believe that this is an entirely separate technology. I think what they do is either separate a growing foetus (whilst very small, only a few cells) or insert a comlete nucleus into a nucleus free cell.

BBCi "The Clone Zone": http://www.bbc.co.uk/science/genes/gene_safari/clone_zone/intro.shtml

Thanks for all your help. Tristan says thanks as well.