What if a genetic screening could foretell how your body would handle HIV—and maybe even predict that you wouldn’t need meds?
Elton Hubbard, an exterminator from South Carolina, has HIV but has never had a detectable viral load or a CD4 count below 900. Of his 1996 diagnosis, he says, “I thought I’d be dead within a year, but it looks like HIV ain’t gonna kill me any time soon. If I’d known, I wouldn’t have gone through years of depression.” Now, Independent Forensics, an Illinois company that tests DNA for paternity suits and criminal cases, suggests that it can spare people the will-I-or-won’t-I anxiety with a genetic test of fluids swabbed from the mouth.
Hubbard, 38, is an “elite controller,” able to suppress HIV without meds. One of a rare breed (fewer than 100 have been identified in the U.S.), he illustrates HIV’s highly variable course, possibly rooted in our genes: Some people progress quickly to AIDS; others move much more slowly. Independent Forensics says its Basepair test can help you determine which of these categories you fall into. But will the test’s information exert any influence on your treatment decisions?
The Basepair test detects some genetic variations affecting CCR5, a protein that HIV uses to enter cells. One variation is the CCR5 delta-32 mutation, found almost exclusively in Caucasians. People with two copies, one inherited from each parent, may be resistant to HIV infection; those with one copy can contract HIV but usually progress to illness slowly. Basepair also detects other CCR5 variations, some of which may affect HIV progression in African Americans.
In an elite-controller study at Boston’s Massachusetts General Hospital, Hubbard learned that he does, indeed, have one copy of the delta-32 mutation. But the study researchers say this doesn’t necessarily explain his good health.
Coordinator Florencia Pereyra, MD, says 15% to 20% of the study’s elite controllers have a copy of the mutation (about the frequency in the general Caucasian population). Pereyra says researchers “don’t know how much this mutation contributes to control of HIV, but we certainly don’t think it explains the whole thing.”
Basepair is certainly alluring. “Everyone should know the valuable information hidden in their genetic code to manage their health,” says the Independent Forensics website. (The company’s chief scientific officer, Karl Reich, PhD, is more modest. “We are not HIV docs, and we do not provide medical advice,” he says.)
Indeed, Basepair’s practical benefits are unclear. For negative people, the test is no guarantee against HIV. Even those with two copies of the CCR5 delta-32 mutation are not immune, since some types of HIV can use a different receptor, called CXCR4. And as the field of medical genetics evolves, the implications for positive people are even hazier. The elite-controller study shows that even with CCR5 mutations, “there is still a huge individual variation in the rate of progression,” says researcher Bruce Walker, MD.
“The test doesn’t really provide you much more info than CD4 count and viral load [do],” Pereyra adds. If your labs are good, it’s unlikely you’d start HIV meds anyway. Further, she says, “There is no way of predicting that a patient with a specific CCR5 profile will not progress.” (If you still want the info the test provides, there’s a special introductory price of $179.99 at www.basepair.info; 866.434.2400.)
Walker wonders how those with a possible slow-progressor profile will react. “Should they delay treatment? Come in every six months rather than every three for a viral load test?” he asks. “Until we have large studies, I’d be reluctant to change clinical practice.” Meanwhile, Elton Hubbard knows his luck is in the genes.
