After years of discussion, the US Department of Health and Human Services (HHS) has released final guidelines describing how synthetic DNA manufacturers should screen customers and the sequences they order to find those who aim to synthesize the genomes of dangerous pathogens.
Draft guidelines released last November prompted concerns from all sides. Some worried that the guidelines would be too strict, and would drive synthetic DNA manufacturers overseas. Others argued that the guidance was not comprehensive enough, and failed to account for all of the techniques and sequences that could be used to create a bioweapon. (For more, see ‘US drafts guidelines to screen genes’)
“This was a time-wasting exercise which consumed too many good people’s energy over nearly a decade,” says Roger Brent, a molecular biologist at the Fred Hutchinson Cancer Research Center in Seattle. “It doesn’t contribute to increased security.”
The HHS guidelines ask manufacturers to screen orders of double-stranded DNA for those that are uniquely found in organisms on the Select Agents and Toxins list, a government list of organisms that pose a potential public health risk. Manufacturers are also asked to screen their customers against government lists of “proscribed entities”, and to notify law enforcement authorities when these screening steps raise concerns.
Industry organizations such as the International Gene Synthesis Consortium have already put together similar guidelines (see ‘Gene-makers form security coalition’). Member companies have notified law enforcement on “a few occasions” says Damon Terrill, senior vice president of Integrated DNA Technologies, a DNA synthesis company based in Coralville, Iowa. “But in all cases it eventually came to light that the concern was unwarranted,” he adds.
The final HHS guidelines differ little from the draft released last year. The provisions of the draft document that generated the most response during the 60-day public comment period were those that dealt with which sequences should be screened, and how. In response to public comment, HHS removed the stipulation that double-DNA sequences covered by the guidelines be at least 200 base pairs long. The final document applies to double-stranded DNA of any length.
Critics also charged that limiting the screening to only the Select Agents list is too restrictive because it fails to consider closely related sequences and sequences that can be found in other organisms as well as in Select Agents. In a preamble to the final regulations, the HHS acknowledges that this is a gap that it was unable to close: “It is not currently possible to develop clear criteria that providers could use to robustly, comprehensively, and consistently identify non-Select Agent and Toxin…sequences of concern.”
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