Using homemade lab equipment and the wealth of scientific knowledge available online, these hobbyists are trying to create new life forms through genetic engineering -- a field long dominated by Ph.D.s toiling in university and corporate laboratories.
In her San Francisco dining room lab, computer programmer Meredith L. Patterson, 31, is trying to develop genetically altered yogurt bacteria that will glow green to signal the presence of melamine, the chemical that turned Chinese-made baby formula and pet food deadly.
"People can really work on projects for the good of humanity while learning about something they want to learn about in the process," she said.
So far, no major gene-splicing discoveries have come out anybody's kitchen or garage.
Critics worry these amateurs could unleash an environmental or medical disaster. Defenders say the future Bill Gates of biotech could be developing a cure for cancer in the garage.
Many of these amateurs might have studied biology in college but have no advanced degrees and aren't earning a living in the biotechnology field.
In Cambridge, Mass., a group called DIYbio is setting up a community lab where the public could use chemicals and lab equipment, including a used freezer, scored for free off Craigslist, that drops to 80 degrees below zero.
Co-founder Mackenzie Cowell, a 24-year-old who majored in biology in college, said amateurs will probably pursue serious work such as new vaccines and super-efficient biofuels, but they might also try, for example, to use squid genes to create glowing tattoos.
Ms. Cowell said such unfettered creativity could produce important discoveries.