Scientists have stumbled upon a novel and path-breaking way to edit our DNAs which may lead to future therapies.

A sophisticated immune system that bacteria use to fight viruses has been unlocked which may provide scientists with unprecedented power to rewrite the code of life, a new research shows.

"It allows customising the genome of any cell or any species at will," Charles Gersbach, assistant professor of biomedical engineering at the Duke University, US, was quoted as saying in a New York Times report.

The molecular system, known as Crispr, is being used to make genetically engineered laboratory animals more easily than before - with changes in multiple genes.

Scientists hope Crispr might also be used for genomic surgery to correct errant genes that cause diseases, said the report.

Agricultural companies might use Crispr to change existing genes in crops to create new traits.

Crispr or 'clustered regularly interspaced short palindromic repeats' is part of an adaptive immune system - one that remembers a pathogen so it is ready the next time the same invader appears.

"The Crispr region is like a tape recording of exposure to prior invaders," said Erik J. Sontheimer, a professor at the Northwestern University.

Cheese and yogurt firms can examine Crispr regions to see if their bacterial cultures are immunised against particular viruses that could slow production.

Some questions, however, have been raised over this method.

For instance, Crispr can sometimes change genes other than the intended ones. That could lead to unwanted side effects, added the report.

Scientists are trying to figure out how to make Crispr more specific.