British scientists have reached a major milestone in their efforts to combat the deadly meningitis bacterium.

Researchers at the Wellcome Trust's Sanger Centre near Cambridge have completed the first stage in determining the genetic blueprint of the bacterium responsible for the most dangerous form of meningitis.

The effort has taken two years and they now have a first stage DNA-map of its genome. However, they do not yet have any information about how the DNA is assembled into genes.

New vaccines

But by sequencing the two million units of DNA which determine how the bacterium is made, they have prepared the ground for new vaccines to prevent the illness.

Dr Julian Parkhill, from the Sanger Centre, told BBC News Online, "This work means that we have laid the foundations for a major leap forward in our understanding of the way this pathogen works."

"Our next step is to look at the DNA data for genes. We expect there may be 2000 genes, some of which will be entirely new to us."

The data are available on the Internet for scientists world-wide to use in their research.

Different strains

Neisseria meningitis comes in several strains, a fact that has made the development of an effective vaccine difficult. A vaccine that works against one strain may not work on another.

The strain of Neisseria meningitis studied at the Sanger Centre was chosen as it causes major epidemics of meningitis in the developing world. It is also extremely closely related to strains that cause outbreaks of the disease in the UK.

The sequencing of a second strain is already underway in the United States.