A Harvard-MIT institute announced a $100 million gift this week to create a new center to study psychiatric disease, in a move that backers say will jump-start the search for the genetic basis of bipolar disorder and schizophrenia.

The Stanley Medical Research Institute awarded the gift—the largest ever given for psychiatric disease research—to the Broad Institute, a three-year-old joint venture between Harvard and MIT.

“There’s no understanding of the causes of these diseases, and that needs to come from collaboration between clinical people and those in neuroscience and genetics,” said Edward Scolnick ’61, who directs the institute’s Psychiatry Initiative and will head the new center. “We can take that on now in a way that would have been impossible without the Stanley grant.”

The money will be donated over a 10-year period to fund research into the genetic causes of psychiatric disease in hopes of discovering viable targets for drug therapy in millions of patients.

The Stanley Institute had given the Broad Institute smaller grants for psychiatric research when Scolnick approached them for funding after joining the institute in 2004, and the organization cited him as an important factor in its decision.

“The gift to the Broad Institute was catalyzed by the presence of Dr. Edward Scolnick,” the Stanley Institute’s Executive Director, Michael B. Knable, said in a statement. He could not be reached for an interview.

Scolnick, a senior lecturer on genetics, saw the Broad Institute’s ability to work with a variety of disciplines in the Boston area as a critical reason for the gift.

“I would emphasize that this was really a large collaborative effort,” he said. “The Stanley Institute recognized that we could engage a really terrific group of collaborators, and that was one of the appeals they found in our proposal.”

The Stanley gift is the third $100 million grant the Broad Institute has received. The other two came from Eli and Edythe L. Broad, who founded the center with their first gift in 2003.

The Stanley Institute is a philanthropy that supports research on schizophrenia and bipolar disorder.

Scolnick said he hoped the funding will enable his center to find novel treatments for these disorders by involving researchers from a wide range of medical disciplines.

“We’re really going after bipolar disorder and schizophrenia that in most part strike young people at the peak of their lives when they’re just getting off the ground,” Scolnick said. “We really can take this on now in an intense and creative way.”

University Provost Steven E. Hyman, who formerly directed the National Institute of Mental Health, said the state-of-the-art approaches that the $100 million gift will pay for represent “our best chance to understand the biological underpinnings of these devastating illnesses.”

“The extraordinary partnership... creates new hope for significant progress that can ultimately be translated into much needed new treatments,” he said in an e-mailed statement.

—Laurence H. M. Holland contributed to the reporting of this story.

—Staff writer Clifford M. Marks can be reached at cmarks@fas.harvard.edu.