Q and A

Question

Can I test for the CCR5 delta 32 deletion that reduces the risk of infection?

It’s a simple question really. Can you get a test to see if you have the CCR-5 delta 32 deletion gene? If so, can you get it from your local GUM clinic in the UK?

Many thanks.

Answer

Not really. The genetic tests are expensive and the only approved test requires shipping a blood sample to the US. They require a lot of hi-tech and skills and usually are used only in the field of research.

10 comments

  1. Simon Collins

    Hi Debra, I am sorry that this isn’t something you can do by blood transfusion. Only a few people with very rare cases of untreatable cancer can try this and most of the time it is not successful.

  2. debra

    Hello,can i get ccr5 delta 32 from blood transfusion??

  3. Roy Trevelion

    Hi Phiona,

    It’s great that you’re on ART and have never been sick.

    So here’s a link to another Q&A about websites where you can meet other HIV positive people. You can click on the links to lots of international users. Perhaps this would be a good place to start.

    Good luck!

  4. Phiona

    AM 30 years have HIV and on art and am health have never fallen sick.My problem is have failed to get a partner of my status, am kindly requesting if you can pleas help me to get some one of my status so that we can get to know each other ,I will be glad if my request is considered . Thank you

  5. Roy Trevelion

    Hi John,

    Thanks for this.

    And we should also remember that those of us who are on ART and stable and undetectable cannot transmit HIV to our sexual partners even if we don’t use condoms. I’m sure you know all about U=U.

  6. John

    I know this is an old thread, but I would like to take the opportunity to warn people of submitting genetic samples to some random company on the Internet. I’ve spent the last few years working for a reputable genomic testing company here in the US that receives & test samples from all over the world; frequently we’re the only company offering a specific test. I’ve heard horror stories from physicians whose patients have been duped into shelling out thousands of dollars only to receive nothing, or even worse, incorrect results. As our capabilities and knowledge increase, so too will the risk associated with this kind of nefarious behavior. There are thousands of bio-tech companies springing up all over the world, take their words with a grain of salt! HIV is 100% preventable through common sense, harm reduction techniques that have been around for decades. Don’t take risks. There is great potential here, lets make sure it goes in the right direction.

  7. Simon Collins

    Thanks Mike. I’m happy to post your comments but not the link to the commercial site providing the test for the same reasons I mentioned above.

    I am very vary of suggesting that this test can be used to know whether you are protected from catching HIV and then changing their behaviour because they think they are safe. Partly this protection is not as great as you are implying.

    Even having the delta-32 deletion in both genes (called homozygous) doesn’t guarantee protection from infection though because HIV can change the use of this coreceptor over time. But far more than 4% of HIV positive people are likely to have virus that uses the CXCR4 coreceptor (called X4-tropic virus), which may relate to people with X4 only, but you need to include the percentage who have mixed and/or dual tropism. Estimates for this vary from about 25-50% of people with late stage infection (or who have been HIV positive a long time), but X4 can also be found at high CD4 counts when people are very well. If someone with the CCR5 genetic deletion gets exposed to X4 virus from someone with dual/mixed tropic virus, they could also become infected.

    See these three articles. The first reports that 8% of recently infected people in one study had X4 mixed virus in early infection. The second is a case report of someone homozygous for delta-32 who still became infected. The third, a paper from JID reporting that X4 can be found even with high CD4 counts (over 450 in this study).
    CXCR4-using HIV found in 8.5% during early HIV infection
    Case report: homozygous CCR5 delta-32 protection overcome by infection with X4 virus
    Emergence and persistence of CXCR4-tropic HIV-1 in a population of men from the Multicenter AIDS Cohort Study

    HIV is generally a difficult virus to catch. But the Wikipedia estimate of 0.04% is not very helpful because risks from sexual exposure range from very low to very high depending on many factors, including viral load, the type of sex, genetics and luck. Although statistically most people who are exposed do not become infected it only takes one exposure for an infection to occur. See this guide to sexual HIV transmission for a non-technical guide to different factors that affect risk in each situation.

    All these factors make finding you are delta-32 homozygous near useless in deciding your risk behaviour if you want to remain HIV negative.

  8. Mike

    Yes, you can get tested for the genetic mutation CCR5 delta 32 using online commercial sites. Once you purchase a kit from the site they will ship you a buccal swab kit and when you ship back a sample of your saliva, they will extract your DNA from the buccal swab. They use PCR to find out if you carry the delta 32 mutation and if you carry one copy of the gene or two. PCR method is very accurate. Simon who posted earlier made a great point that you may still be infected with HIV even if you have two copies of the delta 32 gene which is true but unlikely. HIV uses two ways of entry to CD4, one co-receptor usage is the CCR5 in which if you have two copies of the delta 32 gene you are immune to HIV from entering your cells using CCR5. Another way of entry is CXCR4 which only 4% of HIV infected people account for this type of entry. According to Wikipedia the chances of you getting infected with HIV for each time you have sex with an infected person without condom is about 0.04%. If you have two copies of the delta 32 mutation, the chances are almost zero for you to get HIV but not impossible as you may be infected by CXCR4 tropic but it is so rare that no known cases have been reported and unless you get a blood transfusion from someone who has HIV of CXCR4 tropic which is a rare strains of HIV anyways, you will never get HIV.

  9. Simon Collins

    Yes, although some services offer genetic testing it is difficult to see what benefit this would give an individual. Even if someone has a genetic resistance to most HIV infections, they can still be infected by other strains. i-Base doesn’t provide links to commercial sites unless there is a therapeutic need for HIV positive people.

  10. stance

    Hi yes you can get tested for the CCR5 Delta 32 genetic mutation with some internet-based test services.

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