Summary of Discussions From the 2019 OECD Conference on RNAi Based Pesticides

Michael L Mendelsohn,András Székács,Achim Gathmann,Dimitra Kardassi,Magdalini Sachana,Stephen J Fletcher,Antje Dietz-Pfeilstetter,Stephani Michelsen-Correa,Emily M Hopwood

doi:10.3389/fpls.2020.00740

Abstract

RNA interference (RNAi) is a biological process in which double-stranded ribonucleic acid (dsRNA) molecules inhibit protein expression. In recent years, the application of dsRNA has been used in the development of agricultural products for pest control. The 2019 Organisation for Economic Cooperation and Development (OECD) Conference on RNAi Based Pesticides (“the Conference”) brought together academic, industry, and government experts in various aspects of RNAi to discuss the current state of knowledge and topics to help in developing considerations for risk assessment. The Conference focused on environment, with some discussion of human health. Along with presentations on the use of dsRNA-based products in agriculture, government regulation, risk assessment, and a background on the Draft OECD Working Paper on “Considerations for the Environmental Risk Assessment of the Application of Sprayed or Externally Applied dsRNA-Based Pesticides” (“OECD Working Paper”), the Conference included panel discussions from presenters at the end of each session and a larger discussion session with Conference participants on the environmental fate of dsRNA, non-target organism (NTO) risk assessment, and human health risk assessment. This paper summarizes input from presenters and Conference participants during these discussions. Key considerations from these discussions have already been incorporated into the OECD Working Paper, that once finalized and published, will facilitate regulators in evaluating externally applied dsRNA-based products for potential environmental risks.

Highlights

RNA interference (RNAi) is a biological process in which doublestranded ribonucleic acid molecules inhibit protein expression, typically by triggering the enzymatic cleavage of specific messenger RNA molecules which are templates for protein synthesis (Fire et al, 1998; Agrawal et al, 2003)
Pest control may be achieved by inducing RNAi through topical application of doublestranded ribonucleic acid (dsRNA) onto plants (San Miguel and Scott, 2015; Joga et al, 2016; Cai et al, 2018; Zotti et al, 2018)
The disconnect between predicted dsRNA/transcript sequence homology and physiological effects in part is due to barriers that prevent dsRNA uptake by mammalian cells and the relatively low abundance of discrete short interfering RNAs (siRNAs) derived from a single dsRNA

Summary

BACKGROUND

RNA interference (RNAi) is a biological process in which doublestranded ribonucleic acid (dsRNA) molecules inhibit protein expression, typically by triggering the enzymatic cleavage of specific messenger RNA (mRNA) molecules which are templates for protein synthesis (Fire et al, 1998; Agrawal et al, 2003). In this process, short interfering RNAs (siRNAs) derived from Dicer-mediated cleavage of long dsRNA initiate destruction of an mRNA through complementary base-pairing (Elbashir et al, 2001). Invited speakers included experts in various aspects of RNAi, and their presentations summarized product developments, environmental fate, exposure to externally applied dsRNA in NTOs, lessons from human therapeutic use of dsRNA, and key points from previous regulatory reviews of dsRNAbased crop traits

DISCUSSION

Are there safety concerns with nanoclay particles?

CONCLUSION