Thursday, June 17, 2010

Synthetic Life ... not yet but close

What is life or can we go other way round how you will describe a synthetic life. Creating artificial life is something that every fan of science fiction ponders as a terrifying curtain to be parted—terrifying and at the same time exciting for the potential of such science. If you’ve followed this story at all, or if you are only aware of it in passing, you might enjoy hearing more about the scientist himself, Craig Ventor.

He is called by various names Bad boy of science, Frankenstein Doc, brilliant biologist and shrewd entrepreneur etc. He had the audacity to challenge the US scientific establishment by engaging it in a much-hyped race to map the human genome. And he actually wins the contest time and again. J Craig Venter, Vietnam War veteran, can't seem to stay away from the limelight for long.

Previously, scientists have altered and manipulated DNA piecemeal to produce a variety of genetically engineered plants and animals. But the ability to artificially design an entire genome - the `book of life' that controls an organism's functions - puts a different spin on the meaning of terms such as creation, evolution and life. J Craig Ventor has delivered on a promise he made 15 years ago: to create the world's first synthetic life, a cell controlled by DNA built from scratch in the laboratory. But has he really created a so called synthetic life?

First, the form of life that was created was not new. What was essentially done was the re-creation of an existing bacterial form of life, except that it was given a prosthetic genome (synthesized in the laboratory), and except that the genome was put into the cytoplasm of a slightly different species. It should be emphasized that it will probably be very difficult to make very new forms of life. This is because even the simplest form of life is very complex, so it is very difficult to predict what will happen when you substantially change their genomes. Biologists are nowhere close to imitating what a living cell accomplishes with apparent ease. Venter’s lab essentially copied the code, borrowed existing parts, and depended completely on cell machinery. In effect, they plagiarized living cells.

Second, even if the synthetic genome was substantially different from any existing form of life, one might still object to calling this the creation of new life, because the synthetic cell was made by modifying an existing form of life. Almost all of the material in the synthetic cell comes from a previously existing form of life; only the genome is synthesized. In this respect, one might say that a synthetic cell qualifies as “new” life only if the whole cell is synthesized. If one copies the neighbor’s house, is it an artificial house?

Evolution created life – Venter made an extra copy.But I am not the only one getting worked up about semantics and usage here. Even back home, India's premier geneticist Dr P M Bhargava, who set up the Centre for Cellular and Molecular Biology (CCMB) in Hyderabad, was categorical that Venter, though a fine scientist, had this time around overstated his work's significance. "Venter's team took a cell, removed its DNA and replaced it with a host of other material. This can at best be called a massive bit of genetic engineering.

His words find an echo in the reaction of Dr Steen Rasmussen from the University of Southern Denmark. In a published statement, he said, "Implementing a synthetic genome in a modern cell is a significant milestone in understanding life today. However, the radical 'top down' genetic engineering that Venter's team has done, does not quite constitute a synthetic cell by my definition. Bottom-up researchers, like myself, aim to assemble life — including hardware and the programme — as simply as possible, even if the result is different from what we think of as life. Constructing life using different material and blueprints will teach us more about the nature of life than reproducing life as we know it."

But, one must, for all the sneering, congratulate the team that did this. It was difficult, industrial-scale synthesis. The effort plans to move on to much more purely invented genomes, stripped down and assignable to no specific natural species but equipped for novel jobs. This is a huge accomplishment because it has tremendous implications in genetic engineering. Scientists are already talking about introducing man-made DNA into a certain bacteria so that it be programmed to feed on algae to create biofuels The advance - reported in the journal Science - is, literally, living proof that designer microbes can be built for special jobs, such as producing pharmaceuticals or removing pollutants from water or air. It will undoubtedly take years before a profitable and beneficial organism can be created for widespread use, but I don’t think it’s an exaggeration to say that this technology has the capability to profoundly change the world for the better in the near future.