There are two sets of regulations that cover most Drosophila importation. Federal Plant Pest Regulations (7 CFR part 330) say that the importation of any nonvertebrate organism classified by the U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) as a plant pest is subject to prior approval. Federal Genetically-Engineered Plant Pest Regulations (7 CFR part 340) say that the importation or interstate movement of any genetically engineered plant pest requires prior approval.
The regulations define "plant pest" as any nonvertebrate organism that "that can directly or indirectly injure, cause damage to, or cause disease in any plant or plant product". Consequently, all flies in the genus Drosophila are classified as plant pests for regulatory purposes--even though the vast majority do not injure intact, growing fruit. APHIS scientists clearly understand that many species classified as plant pests under the regulations are not serious plant pests and they tailor their approaches to levels of risk.
Plant Protection and Quarantine (PPQ), which approves the importation and interstate movement of nontransgenic plant pests under 7 CFR part 330, uses a simple application process to approve importation of all strains of all Drosophila species. All shipments imported with a PPQ permit must transit through an APHIS inspection station before delivery to the permit holder.
When 7 CFR part 340 was amended in 2020, transgenic Drosophila melanogaster was exempted from the requirements for import and interstate movement permits in recognition of its low risk and importance to research. Consequently, Biotechnology Regulatory Services (BRS) issues Letters of No Permit Required for importing transgenic strains from any country directly to the permit holder.
There are, however, regulatory provisions that "trump" the exemption and require BRS to give special approval for importation or interstate movement. They are the basis for the four nonroutine strain classes listed on Importation and interstate transportation of nonroutine transgenic Drosophila melanogaster strains.
7 CFR part 340.5(e) explicitly states that the exemption does not apply to transgenic gene drive strains. The importation or interstate movement of any strain with genetic material "designed to propagate through a population by biasing the inheritance rate" must be approved by BRS.
7 CFR parts 340.2(c) & (d) explicitly state that BRS must approve the movement of strains if they have "received DNA from a plant pests...and the DNA from the donor organism either is capable of producing an infectious agent that causes plant disease or encodes a compound that is capable of causing plant disease; or is a microorganism used to control plant pests...and could pose a plant pest risk".
Select agent regulations also trump the exemption in 7 CFR part 340.5(e). Most strains with sequences from select agents require BRS approval for importation or interstate movement. As we discuss elsewhere, strains carrying only ricin A sequences are a recognized exception.
Scientists who have been importing Drosophila awhile will notice that procedures for importing Drosophila melanogaster strains have changed over the past couple of decades. Letters of No Permit Required are more convenient than older permits, which were issued on a country-by-country basis for a limited period of time. The one aspect of importation that is now more complicated is the requirement for distinct documentation for importing nontransgenic versus transgenic flies. Previously, nontransgenic strains could be imported under BRS permits, but this was determined to be a misinterpretation of the regulations. Now, two documents must accompany a shipment containing both nontransgenic and routine transgenic strains. Fortunately, it is easy to apply for both documents. The increased use of PPQ permits will require more shipments to be directed to an APHIS inspection station, but we have not found this to add significant time, trouble or risk to the import process.