A half-synthetic organism

When I was working toward my PhD - way back in the 20th century - I made a lot of use of Yeast Artificial Chromosomes (YACs). These were actually long stretches of cloned human DNA inserted into elements of yeast chromosomes, so that the human DNA could be propagated and maintained in yeast hosts for ease of genomic mapping. By no stretch of the imagination could those yeasts be considered synthetic organisms.

Now it seems we are well on the way to an actual artificial yeast. This report describes a strain of yeast with over half its genome made of synthetic chromosomes; the ultimate aim being to create a completely synthetic genome, that of Saccharomyces cerevisiae 2.0.  These chromosomes are very different to my YACs; not least in that the intention is to provide a functional genome which allows the yeast to survive. The researchers hope to gain a deeper understanding of fundamental biological questions. One aim is to investigate minimal genetic requirements; another to eliminate potential sources of instability in the genome. A greater understanding of how genes and chromosomes combine to make a functioning organism will allow more precise control over engineering of other organisms.

Additionally, although this may seem blue-sky research, the critical role of yeast in industrial biotechnology and other industries means that there are almost certain to be surprising spin-off benefits from this greater understanding of the humble fungus.