Embattled South Korean stem-cell scientist Hwang Woo-Suk won't be able to resume his research for some time due to poor health, his doctor said yesterday.
Hwang, who gained international renown for creating the world's first embryonic stem cells that genetically match injured or sick patients, went into seclusion late last month after publicly apologizing for ethical lapses in his research.
Hwang admitted his team used eggs donated from two junior scientists in his lab, after more than a year of denial.
Under generally accepted international guidelines, scientists are warned to be cautious in allowing subordinates to be subjects for research because of concerns about coercion.
"Prof. Hwang wants to return to his office even now ... but his health has become worse," Ahn Cu-rie, Hwang's physician, who also serves as one of his research partners, told reporters.
"As a doctor, I came to determine yesterday it was impossible for him to return to the office at this point, so I recommended that he recuperates in a hospital," she said.
Ahn declined to give details, citing patient confidentiality. Yonhap news agency quoted her as describing his condition as "more than a cold."
In a vote of confidence for Hwang, President Roh Moo-hyun urged him on Monday to resume his research soon for the benefit of patients suffering from hard-to-treat diseases, and pledged the government's support for his work.
The controversy surrounding the research by Hwang -- a professor of veterinary medicine -- has generated a wave of public support in South Korea, where he is viewed as a national hero.
A group of 1,000 female volunteers yesterday pledged to donate their eggs for research in a ceremony held at Seoul National University where Hwang works.
Meanwhile, new questions have arisen over one of Hwang's human stem-cell experiment that was hailed as a great advance when it was announced in May.
Hwang told the Science journal on Monday that he was correcting some of the photographs that appeared as an online supplement to an article reporting a highly efficient recipe for producing human embryos through cloning, and then extracting their stem cells.
His co-author, Gerald Schatten, of the University of Pittsburgh, said through a spokeswoman that Hwang had not informed him of the problem and that he had asked the university's Office of Research Integrity to conduct an inquiry.
The article, published on June 17, attracted considerable attention because it reported the first step toward the proposed goal of therapeutic cloning.
Hwang said he had converted the adult cells of 11 patients suffering from various diseases into embryonic form, in each case by transferring the nucleus of an adult cell into an unfertilized human egg.
Scientists hope that tissues developed from such embryonic cells could be used to treat a wide range of serious diseases.