BERLIN (Nov. 12) – An American man who suffered from AIDS appears to have been cured of the disease 20 months after receiving a targeted bone marrow transplant normally used to fight leukemia, his doctors said Wednesday.

While researchers — and the doctors themselves — caution that the case might be no more than a fluke, others say it may inspire a greater interest in gene therapy to fight the disease that claims 2 million lives each year. The virus has infected 33 million people worldwide.

Dr. Gero Huetter said his 42-year-old patient, an American living in Berlin who was not identified, had been infected with the AIDS virus for more than a decade. But 20 months after undergoing a transplant of genetically selected bone marrow, he no longer shows signs of carrying the virus.