It is important for you to review the three categories of nonroutine strains below, because, unlike other strains, they raise special regulatory concerns and you may need to provide detailed information in a formal application before being issued a permit. Fortunately, these strains are uncommon.

A USDA division called Biotechnology Regulatory Services (BRS) issues import and interstate movement permits for nonroutine Drosophila strains, or coordinates permits with other agencies. Because these strains are evaluated on a case-by-case basis and the information needed to evaluate each category is different, you should consult with BRS scientists before starting the application process.

Strains carrying transgenic microorganisms causing plant diseases or used for biocontrol of plant pests

BRS says of this class,

"A permit is required for movement of a microorganism carried by Drosophila melanogaster if the microorganism was developed through genetic engineering and it is a plant pest or if the microorganism is used for biocontrol of plant pests and could pose a plant pest risk."

You should contact BRS for advice on importing or moving a Drosophila melanogaster strain carrying a transgenic microorganism that has effects on plant health or that is designed to control plant pests. If BRS judges that the microorganism falls under applicable regulations, it will issue a permit for importing the microorganism, not its fly host. You should be prepared to discuss the genetic details of the fly strain to assure BRS that it would be considered routine without the microorganism.

Strains with select agent sequences

BRS defines this class as,

“Drosophila melanogaster strains that contain introduced genetic sequences from a select agent or an organism that produces a select agent or toxin.”

Select agents are biological agents and toxins that have the potential to pose severe threats to public, animal or plant health and have been chosen for special regulation (see the Federal Select Agent Program). BRS is obligated to consult with other federal agencies anytime a request is made for importation or interstate movement of a transgenic strain with any sequence from a select agent species—even if the sequence has nothing to do with toxins and even if the sequence is not expressed. If a sequence is judged innocuous, no permits will be required. If the sequences raise concerns, BRS will coordinate documentation and permits from the relevant agencies. We strongly recommend that you consult with BRS before contacting other federal agencies.

To our knowledge, the only Drosophila transgenic constructs incorporating sequences from a select agent species are ricin A constructs used in cell ablation studies. While the ricin holotoxin is classified as a select agent, these particular constructs are exempt from select agent regulation, because the ricin A chain does not act as a toxin in the absence of the B chain. In the specific case of a transgenic Drosophila melanogaster strain containing ricin A sequences, but not ricin B sequences, BRS allows importation under a Letter of No Permit Required and interstate movement without a permit.

Strains with sequences capable of biased inheritance

BRS defines this class as,

“Drosophila melanogaster strains where the introduced genetic material is designed to propagate through a population by biasing the inheritance rate.”

A 2020 revision of BRS regulations introduced this rule to assure that strains related to gene drive experimentation were not included in the general exemption of transgenic Drosophila melanogaster strains from permits. The language is broad and subsumes strains with constructs that might not show strong drive, constructs that show drive by means other than CRISPR-related mechanisms and constructs that require combination with other constructs to show drive, but BRS scientists are very good at distinguishing low risk from high risk situations and the advice they will give you regarding permit applications will take risk into account. Contact BRS to discuss genetic details of strains before completing an application.

The import permit application procedure

If you consult with BRS and you are asked to complete a permit application, you will first need to register to use USDA online application forms.

You will use the USDA eFile system to apply for BRS import permits and interstate movement permits. The application process is largely self-explanatory, so, rather than providing step-by-step instructions, we will offer a few tips below. 

• Most academic researchers do not submit applications with Confidential Business Information.
• Starting and expiration dates are typically one year apart.
• The "purpose of the permit" will quite likely be "traditional" research.
• The "means of movement" will likely be mail and/or courier service.
• It is unlikely that any Drosophila strain already has an approved variance or that you will be applying for a variance.
• Labels are formatted eight to a page so they can be printed on 2 x 4 label sheets, so you should request eight labels at a time.

BRS officials can provide advice on filling out more complicated fields and on the contents they would like to see in attachments.