for National Geographic News
Scientists yesterday announced that they have successfully created an entire synthetic genome in the lab by stitching together the DNA of the smallest known free-living bacterium, Mycoplasma genitalium.
Experts are hailing the research as an important breakthrough in genetic manipulation that will one day lead to the "routine" creation of synthetic genomes—possibly including those of mammals.
This is "a striking technical accomplishment," biochemist Leroy Hood, who was not involved in the study, wrote in an email.
"It represents the initial stages of an important new step in studying how genes function together in systems to create complex phenotypes [traits]," added Hood, co-founder of the Institute for Systems Biology in Seattle, Washington.
Step Toward Synthetic Life
The new work is an important second step in a three-step process to the creation of synthetic life, said research leader Hamilton Smith, a biologist and Nobel laureate at the J. Craig Venter Institute in Rockville, Maryland.
The first step, reported last year by the same team at Venter's institute, was the successful transplantation of a genome from one species of bacteria into another, effectively switching the bug's identity.
"The third step, which we're working on now, is to take the chemically synthesized DNA, which is in the test tube, and get it into a bacterium where it can take over and produce a synthetic cell," Smith said.
Researchers liken that step to rebooting a computer, because a genome is akin an operating system that makes a cell function.
Successfully completing the final step would create the first synthetic life-form.
The research is also part of a project to create a cell with "the smallest number of genes that can still confer life," Smith added.
The team chose M. genitalium because it contains about 485 genes, the smallest known of any organism capable of surviving on its own. The researchers suspect that about 400 genes are necessary for life.
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