Artificial genes engineering is one of the most recent innovation in biomedical field. To isolate the pure genes, the scientists used bacterial viruses called bacteriophages, agents that are capable of extracting various genes from the bacteria. Once the genes were sucked into the bacterial virus, the researchers went about the difficult task of separating the ones they wanted from the rest of the genes in the “soup mix.” They did this with an enzyme that digested only the unwanted portion of the DNA, leaving the strand of genetic material they were after.
The article describes the development and characteristics of vivo gene modification techniques developed by NIEHS scientists. The researchers use so callused yeast artificial chromosomes (used in engineering large DNC fragments).Yeast artificial chromosomes contains such sequences as telomeric, centromeric and replication origin. The researchers succeeded in isolating a unit of heredity, the genetic system of which more closely resembles a human’s. The accomplishments have, of course, paved the way toward a better understanding of genes’ behavior and the role they play in defects and disease. There are practical possibilities of another kind. What if scientists could separate the gene that directs the manufacture of silk in a silkworm? Inserted into a bacterium, or into a host of bacteria, such a gene might be stimulated into producing large quantities of the substance for which it is coded. The bacteria would be transformed into busy minifactories, producing insulin to treat diabetes. The steps are not existent now, but when one stops to think about it, with work in higher organisms, it is not inconceivable that in not too long a time this sort of technique could be used. The more you think about it, the more it becomes frightening. “Delitto Perfetto provides a new dimension to YAC cloning of human DNA,” Resnick says, “because it gives one the opportunity to modify genes directly on the YAC without any subcloning process” (Medlin 2002, p. 88). The synthesis is just the beginning step in the investigation of that particular gene. Scientists interested in synthesizing a human gene have some formidable obstacles to overcome. Furthermore, it has been estimated that the chances of getting a virus to transport the right piece of DNA into a cell, using the easiest method known, are about one in one hundred thousand. And even if the DNA does get in, no one really knows how many of an ailing individual’s cells have to be so treated to cure a disease or defect. These problems will undoubtedly be resolved. There is something else about this restriction enzyme. When it is used to slice up DNA, the pieces it produces have sticky ends. This means that when a specific bit of DNA is cut out of a plasmid from a bacterium and then mixed with DNA cut, let us say, from a virus, the sticky ends of each DNA piece glue together. It makes little difference that the DNA sources are different, bacterium or virus. The point is that something new has been constructed. After the two bits of DNA are fused into one, this tiny new genetic package, now known as recombinant DNA, may be easily introduced into bacteria. As the bacteria multiply by division, each new cell that is produced contains recombinant DNA that is exactly the same as that made when the original was glued together. So simple is the technique that any one of you could do it, as long as you or your school chemistry laboratory had some of the enzyme.
The article depicts new ways of biomedical engineering applied to DNA and genes. These developments propose great opportunities for medicine to treat diseases and improve human health. Science can take genetic material from two different sources, join it, and then grow as much of it as desired. This will enable cell biologists to scrutinize genes as never before, increasing their understanding of basic biological processes.
Bibliography
Medlin, J. Delitto Perfetto: Foreign DNA Disappears without a Trace. Environmental Health Perspectives, 110 (1), 2002, 88.-90.