Researchers have found "the strongest evidence so far" that genetic factors can increase the risk of a person developing meningitis. The discovery that gene mutations can determine whether a person develops the disease could help in the search for a vaccine for certain strains.
The findings were made after researchers studied the DNA of 1,500 people with the disease, and 5,000 without, to find anomalies between different groups.
Researchers looked at half a million common genetic variants scattered across each person's genome – which holds information on inheritable traits – and found that some people have differences in their natural defences that make them more vulnerable to contracting the disease.
The results of the study are published in the journal Nature Genetics.
They reveal that those who had developed meningococcal meningitis, a bacterial form of meningitis that affects the brain membrane and can cause death within hours, had markers on a number of genes that were involved in attacking and killing invasive bacteria.
Paediatrician Professor Michael Levin, of Imperial College London, said: "Although most of us have carried the meningitis bacteria at some point, only around one in 40,000 people develop it. Our study set out to understand what causes this small group of people to become very ill while others remain immune. Our findings provide the strongest evidence so far that there are genetic factors that lead to people developing meningitis."