The Viral Threat
New Research from China suggests the latest type of Avian Flu H7N9 may be able to pass from human to human. Previously those infected had only been people who came into close contact with poultry. There has also been a call from virologists to be allowed to experiment freely with the genetics of such viruses. A self-imposed moratorium on research in this field followed concerns over the potential for inadvertently producing new dangerous viral strains - or deliberately producing viral bioweapons.
We put these concerns to Professor David Heymann, who co-ordinated the international response to the global SARS pandemic 10 years ago.
(Photo credit: AFP/Getty Images)
The Genetic Make-up of India's Vast Population
India's caste system is not very old, according to a wide ranging genetic study covering the Indian population. Researchers say there are two main genetic groups in India who mixed for many thousands of years until the introduction of religious and cultural divisions as recently as two thousand years ago.
A Four Billion Year Old Clue
We also look back four billion years to the reconstruction of genetic remnants from the beginnings of life. These have raised the intriguing possibility that life may have first come to earth from elsewhere.