Diet and lifestyle may play a much more significant role in a person's ability to respond favourably to certain drugs, including some cancer therapies, than previously understood, say scientists.
Writing in Nature Genetics, University of Manchester researchers have shown how the nutrients in the environment are critical to the fitness of cells that carry genetic mutations caused by diseases.
The findings for the first time provide a scientific insight into why some people might respond better to certain medications than others and form the foundations for more individualised drug therapy in the future.
The team used baker's yeast – a model organism studied by biologists to reveal molecular processes in higher organisms – to explore the relationship between environment and genetic background.
The large-scale study involved removing one of the two copies of all yeast genes – similar to removing one parent's set of genes in a human – and analysing the resulting fitness under different dietary restrictions.
“If the gene targeted is quantitatively important, you would normally expect the yeast to show a reduction in fitness,” said Dr Daniela Delneri, who carried out the research in the University's Faculty of Life Sciences.
“But what we found was that in certain environmental conditions, removing one copy of certain genes actually produced the opposite effect and surprisingly the yeast cells grew more quickly and were healthier.”
The team further established that this effect was mainly occurring in genes involved in the proteasome – the quality-control system within the cell that degrades unwanted proteins.