How 'hidden mutations' contribute to HIV drug resistance

Jul 31, 2008

One of the major reasons that treatment for HIV/AIDS often doesn't work as well as it should is resistance to the drugs involved. Now, scientists at McGill University have revealed how mutations hidden in previously ignored parts of the HIV genome play an important role in the development of drug resistance in AIDS patients. Their study will be published Aug. 8 in the Journal of Biological Chemistry.

"HIV develops resistance very rapidly, and once that happens, drugs don't work as well as they theoretically should, or they stop working altogether," explained Dr. Matthias Götte, an associate professor in McGill's Department of Microbiology and Immunology. "Physicians routinely have the patient's virus tested for resistance in advance of treatment to help make the appropriate clinical decisions."

The study was conducted by a team of researchers led by Dr. Götte at McGill's Faculty of Medicine, with assistance from the B.C. Centre for Excellence in HIV/AIDS at the University of British Columbia (UBC). It was funded by the Canadian Institutes for Health Research (CIHR).

HIV genotype testing is now widely established in HIV drug resistance screening. However, for technical and economic reasons, the entire HIV genome is usually not sequenced.

"The focus has been on specific areas of the HIV genome where we expect these resistance-conferring mutations to occur," Dr. Götte said. "We focus on a particular sequence on an important gene from amino acid 1 to 300, and as such, we miss roughly a third of this gene. Until recently, most researchers believed that this hidden area was of little clinical significance."

Within the last few years, however, studies started to suggest that the first 300 amino acids alone may not completely describe the drug resistance landscape. Dr. Götte and his colleagues selected a few of these previously uncharacterized mutations and subjected them to a battery of highly sensitive biochemical tests.

"People were skeptical," Dr. Götte said. "The mechanism about how these mutations could be involved in resistance was not clear. However, in our paper, we present data that explains in considerable detail how these mutations work."

Nevertheless, he cautioned, the debate about whether to routinely screen these areas of the HIV genome will still likely continue for some time.

"It's extremely time-consuming and expensive to validate genotype testing," he said. "However, we probably will be testing these areas in a couple of years."

Source: McGill University

Explore further: So much has changed since the first HIV test was approved 30 years ago

add to favorites email to friend print save as pdf

Related Stories

Google hits back at rivals with futuristic HQ plan

53 minutes ago

Google unveiled plans Friday for a new campus headquarters integrating wildlife and sweeping waterways, aiming to make a big statement in Silicon Valley—which is already seeing ambitious projects from Apple ...

Recommended for you

Obese British man in court fight for surgery

Jul 11, 2011

A British man weighing 22 stone (139 kilograms, 306 pounds) launched a court appeal Monday against a decision to refuse him state-funded obesity surgery because he is not fat enough.

2008 crisis spurred rise in suicides in Europe

Jul 08, 2011

The financial crisis that began to hit Europe in mid-2008 reversed a steady, years-long fall in suicides among people of working age, according to a letter published on Friday by The Lancet.

New food labels dished up to keep Europe healthy

Jul 06, 2011

A groundbreaking deal on compulsory new food labels Wednesday is set to give Europeans clear information on the nutritional and energy content of products, as well as country of origin.

Overweight men have poorer sperm count

Jul 04, 2011

Overweight or obese men, like their female counterparts, have a lower chance of becoming a parent, according to a comparison of sperm quality presented at a European fertility meeting Monday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.