• 888-778-6481

    Scientists identify minimum set of genes needed for life

    In a paper published in Science on March 25, researchers led by genome sequencing pioneer Craig Venter report engineering a bacterium to have the smallest genome—and the fewest genes—of any freely living organism. Known as Syn 3.0, the new organism has a genome whittled down to just 473 genes, the bare essentials needed to survive and reproduce. The human genome, in comparison, has between 19,000 and 25,000 genes.
    The microbe’s streamlined genetic structure excites evolutionary biologists and biotechnologists, who anticipate adding genes back to it one by one to study their effects. Synthetic biologist Chris Voigt of the Massachusetts Institute of Technology in Cambridge described this study as “an important step to creating a living cell where the genome is fully 
defined”. But Voigt and other scientist note that this complete definition remains a ways off, because the function of 149 of Syn 3.0’s genes—roughly one-third—
remains unknown. Investigators’ first task is to probe the roles of those genes, which promise new insights into the basic biology of life.
    As Syn 3.0’s name suggests, it’s not the first synthetic life made by J. Craig Venter Institute (JCVI). Venter’s team reported the synthesis of the sole chromosome of Mycoplasma mycoides in 2010 in Science and booted up in a different mycoplasma called M. capricolum. The genetic material in their initial synthetic organism, Syn 1.0, was left unchanged from 
the parent. In their current work, this team led by Clyde Hutchison at JCVI, set out to determine the minimal set of genes needed for life by stripping nonessential genes from the 901 total genes in Syn 1.0. They initially formed two teams, each with the same task: using all available genomic knowledge to design a bacterial chromosome with the hypothetical minimum genome. Both proposals were then synthesized and transplanted into 
M. capricolum to see whether either would produce a viable organism.
    This discovery will lead to a better understanding of the building blocks of life, which could have applications in medicine, biofuels, and agriculture.