New research suggests all of one's inherited traits might not necessarily be a result of DNA.
The findings show proteins found in cells, called histones, could control whether genes are switched on or off, the University of Edinburgh reported. These proteins act as "spools" in which DNA is wound around.
"The research confirms a long-held expectation among scientists that genes could be controlled across generations by such changes. However, it remains to be seen how common the process is," the researchers said.
A team of researchers found naturally occurring changes in these proteins, which are believed to have an influence on how they control genes and even which genes are passed on.
The findings are the first to show that DNA is not solely responsible for which traits are inherited, and the breakthrough could open up the door for research into whether or not these proteins have an influence on health. It could also lead to studies that find whether or not changes to the proteins caused by environmental factors such as stress and diet could influence which genes are passed down.
The researchers made their findings by introducing changes to the histone protein in yeast to mimic those that occur naturally, and found it caused nearby genes to switch off. These effects were then inherited by the next generation of yeast.
"We've shown without doubt that changes in the histone spools that make up chromosomes can be copied and passed through generations. Our finding settles the idea that inherited traits can be epigenetic, meaning that they are not solely down to changes in a gene's DNA," said Professor Robin Allshire, of the University of Edinburgh's School of Biological Sciences, who led the study.
The findings were published in a recent edition of the journal Science and was supported by the Wellcome Trust and the EC EpiGeneSys Network.
