Genes that protect against HIV/AIDS are less common among Indians than 'harmful' genes that promote rapid progression from infection to disease, say researchers at the All India Institute of Medical Sciences.
The researchers looked at 200 HIV-positive and 2,000 non-infected people in India.
They found that a gene called HLA-B*25-Px, which is linked to the rapid progression from infection with HIV to full-blown AIDS, was 2.5 times more common than a protective gene known as HLA-B*35-Py.
The team also found that a protective protein that makes up part of the immune system's defences against infections was absent among the people they surveyed.
Last year, India's National AIDS Control Organisation said there were 5.1 million HIV-infected people in India. The year before that, the United States National Intelligence Council had estimated there were between five and eight million.
Activists say the number of HIV-positive people in India is much higher than its government claims.