German hematologists Eckhard Thiel, left, and Gero Huetter of Berlin's Charite Medical University
attend a news conference about a successful treatment of a HIV infected patient in Berlin, on Wednesday, Nov. 12, 2008. (AP Photo/Michael Sohn)
Doctors in Germany say a patient appears to have been cured of HIV by a bone marrow transplant from a donor who had a genetic resistance to the virus.
The researchers in Berlin said the man, who suffered from leukaemia and HIV, had shown no sign of either disease since the transplant two years ago.
But they stressed it was an unusual case which needed further investigation.
Experts said the result may boost interest in gene therapy for HIV.
Berlin's Charite clinic said the 42-year-old patient was an American living in Berlin, but the man has not been identified.
About one in 1,000 Europeans and Americans have a resistance to HIV