In recent decades, scientists have discovered that many traits in living things are controlled not just by their genetics — what’s written in the code of their DNA — but also by processes outside their DNA that determine whether, when and how much the genes are expressed, known as epigenetics.
This opens up the possibility of entirely new ways to breed plants and animals. By selectively turning gene expression on and off, breeders could create new varieties without altering the genes.
Recently scientists have produced a ‘methylome’ for cotton, a powerful new tool to guide breeders in creating cotton with better traits based on epigenetic changes. It’s an important step towards a new way of improving crops, called epigenetic breeding.
Scientists have produced a “methylome” — a list of genes and genetic elements that have been switched on or off through a natural process called DNA methylation. A methylome provides important clues for biotechnology firms that want to adapt crops through epigenetic modification.
This methylome covers the most widely grown form of cotton, known as Upland or American cotton; its cousin, Pima or Egyptian cotton; and their wild relatives, while showing how these plants changed over more than a million years.
The researchers found that wild cotton contains a methylated gene that prevents it from flowering when daylight hours are long — as they are in the summer in many places, including the United States and China.
In domesticated cotton, the same gene lost this methylation, allowing the gene to be expressed, an epigenetic change that allowed cotton to go global.
