SEOUL, South Korea — South Korea's leading university said today that researcher Hwang Woo-suk did not produce stem cells individually tailored to patients as he claimed he had done in a landmark research paper.

The conclusion was a crushing blow to the disgraced professor's once-vaunted reputation as a cloning pioneer who held the key to medical breakthroughs for hard-to-treat diseases.

A panel from Seoul National University that is investigating Hwang's work said last week at least nine of the 11 patient-specific stem cell lines reported this year in the journal Science were fabricated. Today, the panel said the remaining two were also faked.

"The panel couldn't find stem cells that match patients' DNA regarding the 2005 paper and it believes that Hwang's team doesn't have scientific data to prove that (such stem cells) were made," Roe Jung-hye, the university's dean of research affairs, told reporters.

The latest revelations on Hwang's fabrications are a huge setback for research into stem cells, master cells that can grow into any body tissue.

Creating patient-specific stem cells would be a breakthrough because they would not be rejected by patients' individual immune systems. Scientists hope to someday use those to cure Alzheimer's, diabetes and paralysis.

The panel's interim results also suggested that even the stem cell lines that Hwang claimed to have developed but did not include in the 2005 paper also failed to match patients' DNA, challenging the researcher's insistence that he has the ability to create the tailored stem cells.

Still, Roe said the panel is continuing to consult outside experts on that point. The final results will be disclosed in the panel's concluding report due out in the middle of next month.

Hwang's current whereabouts were unknown and he could not be reached for comment.