“Why do we want to make radical new genomes, rather than making subtle changes that might be sufficient?” he asked. The advantages, he said, include the ability to design new safeguards, new virus resistance and new chemistry.

John Glass, a member of the group at the J. Craig Venter Institute that in 2010 fabricated the first synthetic cell, described his current research.

“It inspired our group to go on from this initial synthetic organism to try to build what we refer to as a ‘true minimal cell,'” he said. Building such a living organism will be an invaluable aid to deeper understanding of basic biological processes, he declared.

Ryan Phelan, a biotechnology entrepreneur, described the efforts of Revive and Restore, a project of the Long Now Foundation, a San Francisco nonprofit dedicated to making “long-term thinking” more common. The project is trying to use genetic engineering techniques to restore the passenger pigeon, a migratory bird that flocked by the billions in the United States before the turn of the last century. The species was hunted out of existence after the invention of the telegraph and railroad made it possible for humans to efficiently track the birds.

She described the increasing rate of “extinction events,” particularly ones affecting bird species.

“The field of conservation is at a low point,” she said. “All you hear is bad stories. What we’re trying to do is bring an influx of technology and hope to the field of conservation.”

But the risks and concerns involved in synthetic biology were made clear by an absence, as much as by the presence of the law enforcement officials and the ambitious aspirations of the scientists who presented. Huanming Yang, chairman of Beijing Genomics Institute, the world’s largest sequencing research institute, was scheduled to deliver the keynote address at the event but was denied a visa by the United States government.

In his absence, the institute’s research was described by Laurie Goodman, editor of Gigascience, a data science journal. She noted that the inclusion of the Chinese research group in the Human Genome Project was the first such Chinese involvement in an international scientific collaboration.