Scientists Create Partly Human Yeast

Posted on May 26, 2015

Biologists from the University of Texas have created partly human yeast. The researchers created strains of genetically engineered yeast using human genes. The researchers say hundreds of genes from an ancestor that the two species have in common live on nearly unchanged in them both.

The scientists say yeast consists of a single cell while humans have trillions of cells. We share thousands of similar genes with yeast. Of these about 450 genes are critical to yeast's survival. The scientists removed the yeast version of each one of these genes and replaced them with the human version. The scientists created hundreds of new strains of yeast, each with a single human gene. The scientists then waited to see if the partly human yeast strains would survive or die. Nearly half of the yeast strains created by the scientists survived and reproduced after having their yeast genes swapped with human genes.

Edward Marcotte, professor in the university's Department of Molecular Biosciences and co-director of the Center for Systems and Synthetic Biology (CSSB), says in a statement, "Cells use a common set of parts and those parts, even after a billion years of independent evolution, are swappable. It's a beautiful demonstration of the common heritage of all living things -- to be able to take DNA from a human and replace the matching DNA in a yeast cell and have it successfully support the life of the cell."

The researchers say the work has applications for human health. Some genetic diseases caused by mutations could be tested in new ways using these partly human yeasts. Scientists could insert precise versions of a human gene mutation into yeast and then expose the yeast to different drugs to test new therapies.

Claus Wilke, a professor in the Department of Integrative Biology and co-author of the paper, says, "We could find out if one of the standard treatments would work on your particular version of the gene or if maybe another drug would be even better."

The scientists think there could be about another 1,000 pairs of swappable genes between humans and yeast. A research paper on the humanized yeast strains was published here in the journal, Science.