Only 473 genes needed to keep organism alive
Credit: E. Otwell; Source: Hutchison et al/Science 2016.
Scientists have built a bacterium that contains the minimal genetic ingredients needed for free living.
This bacterium’s entire set of genetic blueprints, its genome, consists of only 473 genes, including 149 whose precise biological function is unknown, researchers report in the March 25 Science.
The newly-created bacterium contains a minimalist version of the genome of Mycoplasma mycoides. Mycoplasma already have some of the smallest known genomes. M. mycoides used in the experiments started with 901 genes. In comparison, other bacteria, including E. coli, may have 4,000 to 5,000 genes. Humans have more than 22,000 genes, although not all are necessary (SN: 4/2/16, p. 18).