The great gene patenting rush of the 1990s has produced few actual patents, according to a study published today. The findings suggest fears that DNA patenting would inhibit innovation and restrict development of drugs and diagnostic tests were overblown.

Researchers at the UK's University of Sussex found that patent applicationsfor 15,600 human DNA sequences were filed between 1980 and 2003, mainly in the late 1990s when scientists made rapid progress in decoding the human genome. But only a third of the patents were granted by one of the three main patent offices (in the US, Europe and Japan).