Susceptibility gene may influence risk of HIV infection 6/1/05. By the Public Health Genetics Unit People with more copies of a gene that helps to fight HIV may be less likely to become infected with the virus or to develop AIDS than those of the same geographical ancestry (such as European Americans) with fewer copies of the gene.

The study, by researchers at the US National Institutes of Health, was published online by the journal Science.

The research focused on the gene that encodes CCL3L1, a potent HIV-blocking protein that interacts with CCR5 – a receptor protein that HIV uses as a doorway to enter and infect cells. Blood was analysed from over 4300 African-Americans, Europeans and Hispanic-Americans, both HIV-positive and HIV-negative, and the average number of copies of the CCL3L1 gene for each group was determined. These were four, two and three respectively for HIV-negative individuals.

Individuals with fewer than the average number of CCL3L1 genes for their ethnic group were found to be more susceptible to HIV infection, and at an increased risk of between 39 per cent and 260 per cent of rapid progression to AIDS following infection. Individuals with more than the average number of CCL3L1 copies were reportedly less susceptible; each additional gene copy was said to be associated with a 4.5-10.5 per cent reduction in the probability of HIV infection.

The researchers hope that this discovery could lead to a screening test that identifies people who have a higher or lower susceptibility to HIV/AIDS, potentially enabling clinicians to adapt treatment regimens, vaccine trials and other studies accordingly.

Article courtesy of the Public Health Genetics Unit .

Links

Press release

Gonzalez E, et al. (2005) The Influence of CCL3L1 Gene-Containing Segmental Duplications on HIV-1/AIDS Susceptibility. Science 10.1126/science.1101160. Abstract