Paris - French virologists Luc Montagnier and Francoise Barre-Sinoussi, who were awarded the 2008 Nobel Prize for Medicine, will always be associated with the discovery of the retrovirus that causes AIDS.

In 1982, Montagnier headed a team at the Pasteur Institute in Paris, of which Barre-Sinoussi was a member, that was asked for assistance in establishing the possible viral cause of a mysterious new syndrome, AIDS.

Willy Rozenbaum, a clinician at the Bichat Hospital in the French capital, had been openly suggesting that the disease could be caused by a retrovirus. In January 1983, he sent a lymph node biopsy from one of his patients to Montagnier's team at the Pasteur Institute.

Montagnier dissected the lymph node and made a culture from it. In the following weeks, Barre-Sinoussi and her assistants regularly analysed the culture until they determined that retroviral enzymatic activity was responsible for the pathogenic effect of the virus on the white blood cells.

Montagnier and his team named the responsible pathogen lymphadenopathy-associated virus. However, one year later a team led by the US physician Robert Gallo confirmed the discovery of the virus, but renamed it human T-lymphotropic virus type III (HTLV III).

For many years, credit for the discovery of the AIDS virus was a subject of controversy between Montagnier and Gallo, until French President Francois Mitterand and US President Ronald Reagan helped to forge an accord in which both men agreed to share the credit.

In 1986, both the French and American names for the virus were dropped in favour of the term "human immunodeficiency virus" (HIV).

The 76-year-old Montagnier, who was born in the town of Chabris, near Tours, had made a significant number of discoveries before his name became unalterably associated with HIV.

He made major contributions to the understanding of how viruses can alter the genetic information of host organisms, and thereby significantly advanced cancer research.

His investigation of interferon, one of the body's defences against viruses, also made possible subsequent medical cures for viral diseases.

He became interested in science in his early childhood through his father, an accountant, who carried out experiments on Sundays in a makeshift laboratory in the basement of the family home.

Since 1993, Montagnier has been president of the foundation he helped found, the World Foundation for AIDS Research and Prevention.

The 61-year-old Barre-Sinoussi was born in Paris and in 1975 became a researcher at INSERM, the only French public organization entirely dedicated to biological, medical and public health research.

She specialized in AIDS research almost from the beginning of her career, and was instrumental in helping Montagnier discover the AIDS retrovirus.

In 1998, she became head of her own laboratory at the Pasteur Institute. In the course of her career, she has co-authored over 200 scientific publications and participated in over 250 international conferences on AIDS.

She has also worked as a consultant to the World Health Organization and UNAIDS-HIV. (dpa)