Mouldy crust's clue to life

MOULDY bread has helped scientists solve one of life's mysteries - how it began.

A microscopic parasite, hidden inside a mould that thrives on stale bread, could be the 'missing link' to life as it was 3 billion years ago.

The parasite is related to the viruses that cause Aids and types of cancer; the discovery could lead to better anti-viral drugs. Biologists have speculated that before the evolution of DNA - the genetic blueprint of nearly all life today - living organisms used its simpler cousin, RNA, to replicate. Scientists at Ohio State University believe the virus-like 'element' is a descendent of the first life- forms to make DNA from RNA.