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 tattoos that glow.
Cowell said such unfettered creativity could produce important discoveries.
"We should try to make science more sexy and more fun and more like a game," he said.
Patterson, the computer programmer, wants to insert the gene for fluorescence into yogurt bacteria, applying techniques developed in the 1970s.
She learned about genetic engineering by reading scientific papers and getting tips from online forums. She ordered jellyfish DNA for a green fluorescent protein from a biological supply company for less than $100. And she built her own lab equipment, including a gel electrophoresis chamber, or DNA analyzer, which she constructed for less than $25, versus more than $200 for a low-end off-the-shelf model.
Jim Thomas of ETC Group, a biotechnology watchdog organization, warned that synthetic organisms in the hands of amateurs could escape and cause outbreaks of incurable diseases or unpredictable environmental damage.
"Once you move to people working in their garage or other informal location, there's no safety process in place," he said.
Some also fear that terrorists might attempt do-it-yourself genetic engineering. But Patterson said: "A terrorist doesn't need to go to the DIYbio community. They can just enroll in their local community college."