London, Dec 10 (IANS): Scientists from University of Liverpool have created the first map of wheat epigenome which can lead to a new tool to improve crop-breeding technologies.

Epigenetic marks are chemical tags which physically attach themselves to DNA and modify its function without changing the genetic code.

DNA methylation is one such mechanism of epigenetic gene expression control that can be passed down to future generations.

Now, developing technology has allowed scientists to study DNA methylation across the complex and challenging wheat genome.

"Due to the sheer size of the wheat genome, undertaking a survey like this has been technically unworkable until now, but understanding how and when genes are activated is a key part of understanding its complexity," said Dr Laura Gardiner from university's Centre for Genomic Research.

Liverpool scientists created the first draft of the wheat genome in 2012, enabling new levels of precision breeding for this globally important food source which provides 20 percent of daily calories and protein for the world's population.

"This work opens up a whole new level of genetic variation which can be exploited by wheat breeders. In the future we see epigenetic marks becoming an important new tool in this area," she added.

"With the ability to characterise genome-wide patterns of methylation, we can now address fundamental questions in wheat, such as the role of epigenetics in the domestication of crops and the stability and long-term function of methylation," noted professor Anthony Hall who led the study, added.

"We can also seek to understand how methylation changes important traits for farmers like disease resistance and yield variability," he added.

The paper was published in the journal Genome Biology.