HIV

Scientists report that a genetic variation appears to play a major role in slowing disease progression in HIV-infected patients. Those with the variation appear to take years longer to develop AIDS and die of complications of the disease.

AIDS remains a major killer in many parts of the world, but HIV - the virus that causes it - doesn't affect infected people the same way. People progress to AIDS at different rates. Some people progress from infection to disease within a year, while some have been infected for 20 years and still don't have the disease. Three factors affect how the disease strikes a person:

1. Environment - the world in which a person lives,

2. Patient's genetic makeup, and the

3. Genetic makeup of the virus itself.

To see how genetic variations affects AIDS progression in men with HIV infection, researchers looked at the genetic and medical records for 1698 HIV-infected European men.

It was found that a variation linked to higher levels of a protein known as HLA-C boosted the men's ability to avoid progressing to AIDS. It delayed both the progression to AIDS and death by many years. The genetic variation makes it easier for the immune system to kill cells that have been infected with the virus. It does this by allowing immune cells to gain greater access to the infected cells.

Though the above findings clearly indicate that HLA-C levels determine HIV control in men, how this new knowledge will translate into immediate benefits for patients with HIV is not clear.