Washington

A biologist at the Dana-Farber Cancer Institute in Boston has been accused of swindling friends and colleagues out of more than half-a-million dollars to support a non-existent start-up company in China.

But the researcher, 38-year-old Weidong Xu, says that he raised the money honestly to support the study of severe acute respiratory syndrome (SARS) — only to lose it in a Nigerian investment scam.

Xu pleaded not guilty to stealing $160,000 from six colleagues between July and September 2003, in a hearing at Roxbury District Court in Boston on 31 March. Prosecutors allege that he also took $450,000 from almost 30 others.

Arnold Abelow, Xu's lawyer, says that his client fell prey to a Nigerian investment scam that promised to return $50 million on an investment of $600,000. He says that Xu always intended to fund a SARS-research company in his native China, but thought that the project could have a greater impact with the extra money. “He saw a fax in the Dana-Farber office from some people in Nigeria, and he fell for it,” Abelow says.

In a statement, the Dana-Farber Institute said that its officials notified the police as soon as they were aware of the issue. When the police arrived to interview Xu, the court was told, they found him at a cafeteria arguing with another employee, who said he had given Xu more than $5,000. Xu was immediately arrested; he is being held at the Suffolk County Jail in Boston, pending a court hearing on 23 April.

Until last month — when the institute fired him for reasons that it has not disclosed, but says are unrelated to the criminal charges — Xu had spent a low-key but respectable career in AIDS research. He had been at the Dana-Farber Cancer Institute since 1999, when virologist Ruth Ruprecht hired him to look for antibodies that might lead to HIV vaccines.

In 1993, after receiving a master's degree from Beijing Agricultural University, Xu went to Washington State University in Pullman to pursue a doctorate in biochemistry. On completing it in 1997, he joined the laboratory of Flossie Wong-Staal, a prominent AIDS researcher at the University of California, San Diego. “He was good at the bench, especially at molecular techniques,” says Wong-Staal, now chief scientist at San Diego-based biotechnology company Immusol.

As a young biologist, Xu had a keen interest in business, says Thipparthi Reddy, a microbiologist who worked alongside Xu in San Diego and co-authored papers with him. “He was a patents-oriented kind of guy, and he always used to say: ‘I want to work for a company’,” says Reddy, now at Wayne State University, Detroit.