The creation of synthetic DNA may seem like something out of a science fiction movie, but it is quickly becoming a reality. Scientists have developed a yeast cell with a genome that is more than 50 percent synthetic, including the world’s first entirely synthetic chromosome.
While synthetic bacterial and viral genomes have been produced previously, this leap to eukaryotic cells – which contain the genome entirely within a membrane-bound nucleus – is groundbreaking. Yeast was the logical choice for this achievement due to its compact genome of only 16 chromosomes and its innate ability to manipulate DNA.
Unlike previous DNA synthesis efforts, researchers involved in the Synthetic Yeast Genome Project (Sc2.0) focused on creating a “designer” genome. Senior author and Sc2.0 leader Jef Boeke stated, “We decided that it was important to produce something that was very heavily modified from nature’s design. Our overarching aim was to build a yeast that can teach us new biology.”
Making a synthetic genome
The team removed “junk” DNA from the genome, replaced it with new DNA snippets, and rearranged the order of the genes. They also removed tRNA genes, relocating them to an entirely new, t-RNA gene-based “neochromosome”. Co-author Patrick Yizhi Cai described the tRNA neochromosome as “the world’s first completely de novo synthetic chromosome.”
The researchers created 16 partially synthetic yeast strains, each with 15 natural chromosomes and one synthetic, before embarking on the challenge of getting all synthetic chromosomes into a single yeast cell.
Putting the pieces together
After utilizing a combination of interbreeding and new techniques, the researchers successfully achieved a yeast cell with more than 50 percent synthetic DNA. This accomplishment opens a new era of engineering biology, allowing for de novo design and construction of entire genomes.
Next steps
Synthetic DNA has the potential to revolutionize food and drink production, chemical processes, and disease research and treatment. Scientists are hopeful that incorporating synthetic chromosomes into a single yeast cell will lead to even more groundbreaking discoveries in the near future.
The study detailing these advancements is published in the journal Cell.
