Jeremy R. Knowles, dean of the Faculty of Arts and Sciences, has been elected one of the nine trustees of the Maryland-based Howard Hughes Medical Institute, the second-largest philanthropy in the United States.

Knowles will replace George W. Thorn, a professor emeritus at Harvard Medical School, who played a defining role in the development of the Howard Hughes Medical Institute (HHMI) and served at different times as the medical research organization's president, director of research and chairman of trustees.

"[Thorn] was one of the great founders and leaders of the institute," said David Jarmul, associate director of communications for HHMI.

Thorn, who is now in his 90s, had served as a trustee of the institute since 1984 until his resignation last week.

Jarmul said this move was not unpremeditated.

"He had made his intentions known prior to that," he said.

Thorn was unavailable for comment at his residence in Cambridge late last night.

The other eight trustees--who include former Secretary of State James A. Baker III, former University of Chicago president and current Harvard Fellow Hanna H. Gray, and former Du Pont CEO Irving S. Shapiro--discussed the appointment of a ninth trustee and formally elected Knowles last week.

Knowles said he was unaware he was being considered as a potential HHMI trustee.

"I was delightedly surprised to receive a telephone call last week," he said.

Knowles will take office as a trustee immediately, said Jarmul, but he will remain at the helm of the Faculty of Arts and Sciences. Trustees meet only several times a year to discuss the overall direction and policies of the HHMI, allowing them to continue their primary occupations, Jarmul said.

In an interview with The Crimson last night, Knowles expressed satisfaction with his election.

"I am, of course, honored and delighted to have the opportunity to serve a [medical research organization] that provides such magnificent support for research in the medical and life sciences in this country," he said.

However, he declined to elaborate on his goals for his new appointment.

"It would be presumptuous and improper to embark on my trusteeship with an agenda," he said.