What's Life Coming To?
Life created in a lab is no longer just the work of science fiction writers. Man-made life is now a reality. World-renowned geneticist Dr. Craig Venter, along with his team at the J. Craig Venter Institute in Maryland, has created the first “synthetic” life form: a modified version of the simplest bacteria.
Dr. Craig Venter launched himself into the elite science community in 2001 when he released into the public domain a decoded human genome. Since then, he’s turned his efforts to another grand project: to create a synthetic life form, a dream he’s had for 15 years. Yesterday, he announced that his team has successfully accomplished this feat.
While the team is calling this a synthetic life form, it is only the DNA in the cell that is completely man-made. So in reality, Dr. Craig Venter has created the first organism to be entirely controlled by synthetic DNA, not a completely synthetic life-form. So they have not created life from scratch.
A cell, the simplest unit of all biological life, is made up of many components suspended in a fluid called cytoplasm and contained within a thin membrane called the cell wall. Each of these components performs a function necessary for life to exist, such as converting food to energy and disposing of waste materials. At the centre of the cell is a nucleus which contains the unique genetic material of that organism, called DNA (Deoxyribonucleic acid). When a cell splits, or replicates, all of the components, including the DNA, are copied exactly.
DNA is made up of four building blocks called nucleotides which exist in various sequences. It is the sequence of the nucleotides, or genetic code, that dictate the characteristics of an organism. What Dr. Venter’s team did was artificially construct DNA using the genetic code from Mycoplasma genitalium, the world's smallest bacteria that lives in cattle and goats. They stored this information in a computer, and then slightly modified the DNA sequence so that it was distinguishable from the original. They then developed a technique of stripping the original bacteria of its DNA and replacing it with the synthetic form. The resulting cell was then “rebooted” so that it began replicating again.
Dr. Craig Venter compared this method to building a computer. Making the synthetic DNA was like writing software for the computer’s operating system while transferring it to the cell was like loading the software into the hardware and running the program.
While this “synthetic” organism is simple, only having 485 genes (compared to a human genome which is made of 20,000 genes), it is the beginning of a process that could lead to the creation of more complex species. But what does this mean for the scientific community, or the Earth as a whole?
Some see this new technology as having the potential to drastically improve the quality of life for humans. Suggested applications include creating organisms that could aid in carbon capture, could clean water sources, could lead to new fuel sources, or could aid in faster vaccine production. However, others fear negative consequences, such as the production of new biological warfare tactics.
Dr. Craig Venter is taking the controversy in stride, stating that all technologies have the ability to be used for good or for bad. A hammer can be used to build a house, but can also be used as a weapon, he points out. Dr. Venter also stresses that he and his colleagues have been addressing these ethical issues since they began their first experiments. "We think these are important issues,” Venter confirms, “and we urge continued discussion that we want to take part in."
When you’re visiting the TELUS World of Science stop by our Health Gallery where will show you how to extract DNA from a banana and discuss the topics or cell biology and artificial life.
More information on the topic can be found in the Edmonton Journal, May 21, 2010 here.
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