03/06/2012 12:15 pm ET

Psoriasis Linked to Protection from HIV-1, Study Finds

By Charles Q. Choi
(Click here for the original article and podcast)

Psoriasis is an autoimmune disease—the immune system mistakenly attacks its own body, causing red, itchy, scaly patches on the skin. But there may be a hidden upside. People with psoriasis are more likely to have gene variants that protect them against the effects of HIV-1.

Researchers had noticed that some psoriasis patients had the same gene variants as people known as "HIV-1 controllers." Such people have HIV-1, but they naturally maintain low levels of the virus and generally do not develop any obvious symptoms of AIDS.

To investigate further, scientists looked at more than 1,700 psoriasis patients and nearly 3,600 people who don’t have it. People who have psoriasis were significantly more likely to have the gene variants known to defend against HIV-1 and delay its progression to AIDS. The study is in the journal Public Library of Science Genetics. [Haoyan Chen et al.,"Psoriasis Patients Are Enriched for Genetic Variants That Protect against HIV-1 Disease"]

These findings suggest that psoriasis is a malfunction of antiviral gene variants that ordinarily protect us against disease. Further research could help us understand why autoimmune diseases develop, and give researchers new tools for treating HIV.