The Fertility Show, Manchester Central, 24-25 March 2018
Page URL:

Gene variant increases Africans' HIV risk

21 July 2008
Appeared in BioNews 467

A form of a gene that protects many Africans from certain forms of malaria increases HIV (human immunodeficiency virus) infection risk, according to a new study published in the journal Cell Host and Microbe. Researchers Professor Sunil K Ahuja, from The University of Texas Health Science Center at San Antonio, and Professor Robin Weiss, from University College London's department of Infection and Immunity, drew their conclusions from genetic data collected during a 25-year study of 3,400 Americans of different ethnic backgrounds.

The gene involved encodes a receptor protein, called DARC (Duffy antigen receptor for chemokines) that is expressed on blood cell surface. Chemokines are chemical messengers used by the immune system to coordinate inflammation. Malaria can use DARC to infect red blood cells. The variant gene common in Africans carries a mutation leading to a loss of DARC expression, preventing malaria from gaining a foothold. However, DARC also influences HIV infection. 'The big message here is that something that protected against malaria in the past is now leaving the host more susceptible to HIV', said Professor Weiss. He continued: 'In sub-Saharan Africa, the vast majority of people do not express DARC on their red blood cells and previous research has shown that this variation seems to have evolved to protect against a particular form of malaria. However, this protective effect actually leaves those with the variation more susceptible to HIV'.

The research shows a 40 per cent increase in the risk of HIV infection in African-Americans with the DARC mutation, compared to those with normally expressed DARC. The study goes some way to explaining the devastating impact of HIV on sub-Saharan Africa. Genetic susceptibility, not social factors alone, may account for the high rates of infection. This is the first uniquely African genetic link to HIV to be identified. A mutation in another chemokine receptor, called CCR5, was previously found to confer increased resistance to HIV in around one per cent of Caucasians.

Surprisingly, the researcher found that individuals with the DARC variant who become infected with HIV live slightly longer than HIV-infected individuals with non-mutant DARC. The reasons for that remain unclear, says Weiss. The findings could have implications for the understanding and treatment of HIV and AIDS. However, further work on different populations needs to be done to confirm the findings.

'This is a provocative paper that will stimulate research in the field', says Cheryl Winkler, who studies the genetics of infectious diseases at the US National Cancer Institute in Maryland, adding: 'but I don't believe this is a done deal'.

African mutation may increase HIV infection
Nature News |  16 July 2008
Common gene makes Africans more vulnerable to HIV
The Guardian |  17 July 2008
Genetic Variation Increases HIV Risk In Africans
ScienceDaily |  17 July 2008
Malaria gene 'increases HIV risk'
BBC News Online |  16 July 2008
30 November 2015 - by Ayala Ochert 
Using 'gene drive' technology, scientists have created mosquitoes with malaria-resistant genes that could spread rapidly into wild mosquito populations, potentially wiping out the disease in some areas...
30 August 2011 - by Dr Kimberley Bryon-Dodd 
Cross-breeding with early humans was highly advantageous to the modern human immune system, according to a new study published in Science...
4 July 2011 - by Mehmet Fidanboylu 
New research has revealed that a group of generic anti-HIV drugs may be linked to premature ageing. The study, which was carried out by UK scientists at the Institute of Genetic Medicine at Newcastle University, could explain why people treated with this class of drugs sometimes show signs of age-related conditions, such as heart disease and dementia....
23 August 2010 - by Victoria Kay 
Researchers have come one step closer to being able to predict who will develop full-blown symptoms following infection with the tuberculosis (TB) bacterium...
16 August 2010 - by Chris Chatterton 
Researchers have discovered genetic factors that they believe are associated with an increased susceptibility to the bacterial form of Meningitis....
28 June 2010 - by Ben Jones 
The Wellcome Trust has joined forces with the US National Institute of Health (NIH) to coordinate a major new genetics study in Africa....
23 February 2009 - by Ben Jones 
A phase 2 trial for a radical new, 'one shot' treatment for HIV has shown small but promising results. The research at the University of California, Los Angeles (UCLA), was published in the journal Nature Medicine and was described by the study leader Professor Mitsuyasu as a...
Log in to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.