In Science this week, a multi-institute team of investigators reports on their efforts to replace multiple codons genome-wide in the bacteria E. coli. The researchers aimed to reduce the number of codons in the E. coli genome to 57 from 64, and replaced more than 60,000 instances of seven codons with synonymous alternatives across all protein-coding genes. They validated 63 percent of recoded genes and found that 91 percent of tested essential genes retained functionality with limited fitness effect. While they fell short of their goal of a 57-codon E. coli, the work demonstrates "the feasibility of radically changing the genetic code and the tractability of large-scale synthetic genome construction."
And in Science Translational Medicine, researchers from the University of California, Davis, and elsewhere discuss in an editorial the importance of animal models in advancing precision medicine in humans. While the Precision Medicine Initiative and other efforts to advance personalized medicine naturally rely on human genetic data, the trove of genetic and molecular data from animal studies could prove useful, they say. Specifically, animal model data could prove extremely valuable when it comes to gene variant interpretation, studying the effects of environmental exposures, and integrative in vivo modeling, among other things, they argue.