A major breakthrough in molecular biology has recently been reported from the laboratories of Dr. J. Craig Venter at the J. Craig Venter Institute in Rockville Maryland and San Diego California. The investigators in this ten year project have successfully synthesized a bacterial chromosome using the DNA sequence data from a species of microorganism called M. mycoides and subsequently introduced this product into a different bacterial species, M. capricolum replacing its DNA with the synthetic variety. This wholly modified organism grew and divided with the characteristics of the donor species.
The technique that was utilized is outlined below:
• A copy of the chromosome of M. mycoides was made by using yeast cells to assemble the DNA in stages. This was an arduous and time-consuming project that required much trial and error.
• The fully synthetic copy was then placed into the recipient microbial species M. capricolum. In order to show that the synthetic chromosome was successfully introduced, the investigators purposefully incorporated into the synthetic product DNA sequences that spelled out in genetic code the e-mail addresses and the names of many of the people involved in the project. In addition, a gene was introduced into the synthetic DNA with the information to produce a blue gene product that would make bacterial colonies visible.
After months of thwarted attempts, blue bacterial colonies were found growing, indicating success. It should be made clear that this breakthrough does not constitute the creation of a synthetic life form, since the bacterial cell machinery was already pre-existing. However, it does demonstrate that the transformation of one bacterial species to another is feasible through the technique that is outlined above, and that it may be possible to introduce synthetic genes capable of producing novel gene products into synthetic bacterial chromosomes and produce organisms with new capabilities such as producing pharmaceuticals or neutralizing chemical pollutants, etc. In addition, this technology also brings with it serious ethical considerations that need to be addressed as well.
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