A group of "Designer DNA" companies is stepping up security over fears that terrorists may turn to designer DNA to create a deadly virus.
According to a report in New Scientist in 2005, some gene synthesis companies were not checking their orders for potentially dangerous DNA sequences.
Since then, the US National Science Advisory Board for Biosecurity has called for better screening.
Now, the Industry Association of Synthetic Biology (IASB) has said that its members will carry a seal of approval on their websites confirming that they do screen their orders.
This is to encourage researchers to order DNA only from these companies, and put pressure on the minority of firms that cut costs by not screening to change.
Companies will display a seal of approval confirming that they screen their DNA orders.
IASB members will cooperate to improve the software used to identify suspicious orders and will set up a secure database detailing which DNA sequences make pathogens highly virulent.
"The fact that they're going to share their experiences is really important," said Stephen Maurer, a lawyer at the University of California, Berkeley, who helped write the industry guidelines.