How Life Impacts Our DNA: New Method Maps Environmental Effects

How does life affect our DNA? Understanding exactly how living life and how environmental factors impact the genes we inherit from our parents is an important part of predicting what traits will develop. Now, scientists have developed a new single-cell technique to help investigate these effects on DNA.

The new technique can be used to map all of the "epigenetic marks" on the DNA within a single cell. These marks are chemical tags or proteins that mark DNA and act as a kind of cellular memory. While they don't change the DNA sequence, they do record a cell's experiences on the DNA, which allows cells to remember an experience long after it has faded. These tags are a normal part of development and tell genes whether they should be switched on or off.

The single-celled method analyzes DNA methylation, which is one of the key epigenetic marks, across the whole genome. The method treats cellular DNA with a chemical called bisulphite. Treated DNA is then amplified and read on high-throughput sequencing machines to show up the location of methylation marks and the genes being affected. The treated DNA is then amplified and read on high-throuput sequencing machines to show the location of methylation marks on the genes being affected.

"The ability to capture the full map of these epigenetic marks from individual cells will be critical for a full understanding of early embryonic development, cancer progression and aid the development of stem cell therapies," said Gavin Kelsey, one of the researchers, in a news release. Epigenetics research has mostly been reliant on using the mouse as a model organism to study early development. Our new single-cell method gives us an unprecedented ability to study epigenetic processes in human early embryonic development, which has been restricted by the very limited amount of tissue available for analysis."

The findings will help researchers define how epigenetic changes in individual cells during early development drive cell fate.

"Our work provides a proof-of-principle that large-scale, single-cell epigenetic analysis is achievable to help us understand how epigenetic changes control embryonic development," said Kelsey.

The findings are published in the journal Nature Methods.