According to a study it was found that a mutation led to the deadly change from benign SIV in apes and monkeys to a deadly infection called AIDS in humans. Statistics show that the disease in man has killed more than 25 million people in 25 years. The researchers said that the virus appears to have been mutated which resulted in the loss of an immune system proactive mechanism in apes and monkeys. The study results were published in the journal Cell.
It was found that the Nef function which conferred immunity in monkeys infected with SIV from causing the disease. The lead authors were Frank Kirchhoff of the University of Ulm in Germany and Dr Beatrice Hahn of the University of Alabama at Birmingham. They said HIV descended from a chimpanzee virus called simian immunodeficiency virus (SIV).
But in case of SIV the monkeys though were infected with the virus did not develop the disease. But so was not the case with HIV as it destroyed the human immune system, leading to AIDS. The nef gene and its protein product were found in all SIV and HIV strains. The virus attack the T-cells especially the CD4 helper T-cells and destroys them by apoptosis. But in the SIV version apoptosis is shut down by another mechanism and there is prevention of the death of T-cells. It is said that during viral evolution this function could have been lost by the HIV-1. This study could open up new ways to HIV.