(May 22, 2015)
Despite a billion years of evolution separating humans from the baker’s
yeast in their refrigerators, hundreds of genes from an ancestor that the two
species have in common live on nearly unchanged in them both, say biologists at
The University of Texas at Austin. The team created thriving strains of
genetically engineered yeast using human genes and found that certain groups of
genes are surprisingly stable over evolutionary time.
The research, published May 22 in the journal Science, paves
the way for using humanized yeast to better understand genetic disorders and to
screen drugs for treating the diseases.
Although yeast consist of a single cell and humans have
trillions of cells organized into complex systems, we share thousands of
similar genes. Of those, about 450 are critical for yeast’s survival, so
researchers removed the yeast version of each one and replaced it with the
human version and waited to see whether the yeast would die. Creating hundreds
of new strains of yeast, each with a single human gene, resulted in many newly
engineered strains — nearly half, in fact — that could survive and reproduce
after having human genes swapped in for their ordinary ones.