ARC Centre of Excellence in Synthetic Biology

Synthetic Biology

News

9, Jan 2024

SynBio, a tool in conservation

The number of wild organisms worldwide is rapidly diminishing in what is sometimes referred to as the sixth major extinction event. As population numbers decrease, the existing genetic variation in wild populations also disappears. This leads to inbreeding and can contribute to extinction. Another risk of this loss in variation means that these populations become more vulnerable to environmental change caused by humans. These include habitat loss, invasive species, exposure to novel pathogens and climate change. While larger populations with more genetic variation (and more adaptive potential) are better equipped to respond to these stressors, smaller populations are highly susceptible.

One way to protect wild populations and allow them to respond to these stressors is to cultivate phenotypic features that will enable them to avoid extinction.

In a paper recently published on Taylor & Francis Online titled ‘Synthetic Biology and the Goals of Conservation’, Research Fellow Dr Chris Lean from our Sydney University node argues for the conservative use of synthetic biology in conservation and the need to re-evaluate our ethical concepts of conservation at times of global environmental and technological change.

‘A lack of urgency in conservation now will undoubtedly result in extant biodiversity loss. This issue of complacency in the face of the biodiversity crisis is the same as faced by climate change where, instead of reducing emissions now, governments are increasingly relying on intensive technological interventions to remove carbon from the atmosphere,’ says Dr Lean.

While ‘assisted evolution’ through selective breeding programs can be effective, genetic variation needs to already exist with the genetically-influenced traits that can be bred through the target population. Smaller populations are less likely to have this genetic variation. Selective breeding is also inefficient; it takes many generations of breeding to isolate the advantageous features. It takes time and also involves many hours of manual work, driving the costs up. It can also lead to the loss of variation in non-associated traits. Removing multiple individuals from their natural habitat in small populations could also endanger that species further.

Gene editing to introduce a new variation is more precise and avoids many of the drawbacks of selective breeding. Biotechnology Assisted Restoration (BAR) is an intervention where wild populations have permanent changes to their features, allowing them to respond to and survive the human-affected environment. Restoring biodiversity with an ongoing, evolving lineage could effectively protect the population.

One example of a BAR project underway is to protect coral against climate change. Increased temperature leads to coral bleaching, which will eventually kill the coral. Large sections of the earth’s coral reefs and associated habitat are at risk of being destroyed. Scientists have been working to introduce genes for heat shock proteins that allow coral species to respond to temperature increases. This program is an example of one that has clear advantages and has received public support.

Synthetic biology has great capacity to aid conservation. However, given the diversity of projects underway using the science, there are risks to consider, both moral and practical. Dr Lean believes conservatism in design, e.g. not making any further changes than what is necessary for the species survival, will mitigate the risk of unintended consequences and make synthetic biology conservation projects more acceptable to the public.

‘There is a cost of inaction and not using the available technology and resources to address current environmental damage. In the case of using biotechnology for biodiversity preservation, small changes in a lineage’s DNA and functional features can preserve that lineage’s features and deep evolutionary history,’ explains Dr Lean.

Photo: Coral reef from Iriomote Island, Okinawa Prefecture, Japan by Hiroko Yoshii on Unsplash