Overlooked Mutation Can Spur HIV Drug ...( It should be added to standard geneti...),Health

It should be added to standard genetic tests used to guide treatment, experts say

SATURDAY, Dec. 1 (HealthDay News) -- One in 10 HIV-infected people receiving drug treatment harbors a hidden genetic mutation that renders certain strains of the virus more resistant to antiretroviral medications, researchers say.

Their study suggests that the N3481 mutation should now be added to standard HIV gene tests that AIDS specialists use as they decide which cocktail of drugs a patient should receive.

"The importance of N3481 is also underscored by the fact that it appears relatively early after starting drug therapy," noted study senior author Gilda Tachedjian, head of the Molecular Interactions Group at the Macfarlane Burnet Institute for Medical Research and Public Health, in Melbourne, Australia.

The mutation, largely overlooked by researchers, appears to confer resistance to zidovudine (AZT or Retrovir), the first drug ever approved to fight HIV; and nevirapine (Viramune), one of a group of powerful antiretroviral medications.

Both medicines fall into a broad category of drugs called reverse transcriptase inhibitors (RTIs), so named because they target a key enzyme on HIV called reverse transcriptase.

Tachedjian's group published its findings late Friday in the December issue of PLoS Medicine on the eve of World AIDS Day.

Gene tests aimed at gauging a particular strain of HIV's resistance to common AIDS drugs are routine in clinical practice, noted Mattias Gotte, an associate professor of microbiology and immunology at McGill University in Montreal. Gotte is also the author of an accompanying commentary in the journal.

"You go as an infected person to a clinician, and you get a certain regimen. Most of the time the clinician uses genotyping [gene tests] to see whether certain preexisting mutations may compromise therapy," he explained. "The other thing that happens is when
'/>"/>