Dean H Hamer of the National Institute of Health and the National Cancer Institute, in an interview to the Washington Post, claimed that chemicals in the brain associated with emotions like joy, sadness and anxiety played a key role in the deep meditative states of the spiritually inclined.

"These chemicals are responsible for the mystical trances experienced by Buddhist practitioners, Roman Catholic nuns and even users of mind-altering drugs like payote," he says.

According to Hamer's research, at least one gene, VMAT2 - which he calls 'God Gene' - controls the flow of chemicals, that play a key role in emotions, to the brain.

"There are probably dozens or hundreds of such genes, yet to be identified, involved in the universal propensity of transcendecnce," he claimed in the interview.

Hamer's previous research on the genetic basis of behavioural traits like anxiety, thrill-seeking and homosexuality encouraged him to look into the genetic propensity for relegious belief.

The latest findings were summed up in his book "The God Gene-How faith is hardwired into our genes," that figured as a cover story in the October issue of Time magazine.

Though various relegious leaders have welcomed the idea of a genetic basis for spirituality, saying it validated long-held teachings, critics in the scientific community dismiss Hamer's conclusions as "simplistic and speculative."