A designer plague that would only kill Serbs or a toxin engineered to affect Israelis or Kurds does not exist yet but advances in biotechnology and the mapping of all human genes could be misused to develop lethal weapons within five to 10 years.

Dr Vivienne Nathanson, the head of health policy research at the British Medical Association (BMA), said yesterday genetic information is already being used to enhance biological weapons.

``It would be a tragedy if in 10 years time the world faces the reality of genetically engineered and possibly genetically targeted weapons,'' she told a news conference to launch a new book entitled Biotechnology Weapons and Humanity.

The book by Prof Malcolm Dando, of the department of Peace Studies at the University of Bradford in Northern England, paints a terrifying picture of the power ofbiological weapons. The release of 100 kg of anthrax spores from canisters planted in a major city could wipe out up to three million people.

The designer weapon works on a similar principle to gene therapy but instead of replacing faulty genes that don't work it exploits genetic variations to target its victims.