Why use yeast in research?

Key facts

• Saccharomyces cerevisiae is a type of yeast, a single-celled organism. It is commonly used in the bread-making industry.
• It is one of the simplest eukaryotic (consists of cells that contain a nucleus) organisms.
• The complete genome sequence of Saccharomyces cerevisiae was published in April 1996.
• Its genome is 12,157,105 base pairs in length and contains 6,692 genes (Ensembl).
• Studying the biology of this yeast has enabled scientists to work out the connections between genes and proteins, and the functions they carry out in our cells.

Benefits of yeast

• Although it may seem that yeast and humans have little in common, yeast is a eukaryotic organism. This means that, like our cells, yeast cells have a nucleus that contains DNA packaged in chromosomes.
• Yeast cells share many basic biological properties with our cells.
• Genetic manipulation in yeast is easy and cheap compared to similar experiments in more complex animals such as mice and zebrafish.
• At least 20 per cent of human genes known to have a role in disease have counterparts in yeast. This suggests that such diseases result from the disruption of very basic cellular processes. For example, genes involved in yeast cell division are mutated in human cancers.
• Yeast shares some genes with humans so can also be used to test new drugs. Thousands of drugs can be tested on yeast cells containing mutated human genes to see if the drugs can restore normal function.
• The genes with the most similarities shared between humans and yeast, are the MSH2 and MLH1 genes. These genes are involved in hereditary non-polyposis colorectal cancer in humans. Examining these genes in yeast helps scientists to learn more about the role of these genes in colon cancer.