Intentional introgression of a blight tolerance transgene to rescue the remnant population of American chestnut

Abstract

In contrast to many current applications of biotechnology, the intended consequence of the American Chestnut Research & Restoration Project is to produce trees that are well‐adapted to thrive not just in confined fields or orchards, but throughout their natural range. Our primary focus is on disease tolerance, but we believe it will also be critically important that optimal restoration trees should have robust genetic diversity and resilience, which can be supplied by a full complement of their wild‐type genes. Chestnut restoration offers a unique case study because many restoration or intervention options have been attempted: doing nothing, planting non‐native chestnut species, planting hybrids, mutagenesis (exposing seeds to high levels of radiation to induce random mutations), backcross breeding, and now genetic engineering. Any of these techniques may be advantageous independently or in combinations, depending on the specific goals of land managers or restoration practitioners, but genetic engineering offers a unique opportunity to enhance blight tolerance while minimizing other changes to the genome.

Exploring the intersections of governance, constituencies, and risk in genetic interventions

“…Stakeholder engagement, however, goes beyond transparency about decision-making to include active engagement that solicits input during the decision-making process. Engagement is an important part of both traditional interventions (Smith & Peterson, 2021) and genetic interventions (Newhouse & Powell, 2021) and has been defined as "Seeking and facilitating the sharing and exchange of knowledge, perspectives, and preferences between or among groups who often have differences in expertise, power, and values" (NASEM, 2016: 131). In the context of this article, it should include discussion about the nature of genetic interventions, their consequences, risks, and permanence, and whether they can be reversed or halted.…”

“…The workshop addressed commonalities across these approaches, while recognizing heightened attention and concern around the use of advanced biotechnology. In this article, we focus on this more controversial subset of genetic interventions for conservation benefit, which could include creation of hybrids to increase viability (Hirashiki, Marvier, & Kareiva, 2021), genetic modifications for invasive species control (Teem et al, 2020), and facilitated adaptation (Newhouse & Powell, 2021). These newer practices can complement conventional conservation methods (Novak, Maloney, & Phelan, 2018;Supple & Shapiro, 2018).…”

Editing the wild

“…Such ideas of the “unnatural” character of gene editing are potentially highly effective in campaigning and are likely to shape public understanding of, and reaction to, genetic engineering for conservation purposes just as it will for commercial applications. Evidence for this can already be found in some negative reaction to the use of genetic engineering to create blight‐resistant American Chestnut ( Castanea dentata) by the insertion of a gene from wheat which produces an enzyme with antifungal properties (Newhouse & Powell, 2021; Smolker & Peterman, 2019; Taylor, 2018).…”

Conservation science and the ethos of restraint

“…The thesis of this special issue of Conservation Science and Practice is that biotechnology and conservation genetics are under-utilized tools capable of slowing species loss and the erosion of biodiversity. Articles in this issue identify and evaluate successful translocations (Smith & Peterson, 2021), the potential for genetic modification to rescue species like the American chestnut (Newhouse & Powell, 2021), and the need to systematically collect and standardize evaluative data on these forms of conservation interventions (Novak, Phelan, & Weber, 2021). All these approaches resist what we call an ethos of restraint: an attitude of excessive precaution that threatens to miss opportunities for advancing conservation goals by restricting the implementation of novel conservation techniques.…”