Genes key in toad war

But professor says to keep magic bullet in reserve

ADVANCED gene editing technology could eradicate Australia’s cane toad problem, but the country’s leading toad expert thinks it might be too risky.

Eminent evolutionary biologist Professor Rick Shine has told a parliamentary inquiry that while genetic manipulation could be the “only technology that might achieve the eradication of cane toads”, the technique “would be difficult to justify” due to “ecological impact”.

But former Darwin Lord Mayor and toad expert Graeme Sawyer has refuted Prof Shine’s conclusion, telling the NT News gene manipulation technology would be “essential” in the fight against cane toads.

“I think when you consider the damage toads have done to our environment, we need to take this step,” Mr Sawyer, a co-ordinator at FrogWatch NT, said.

In his submission to federal parliament’s “Inquiry into controlling the spread of cane toads”, Prof Shine tabled a four-point plan to minimise cane toad impact which omitted gene manipulation as a viable option.

Aussie scientists are close to a breakthrough with such technology, most notably a gene-driver named CRISPR.

CRISPR, developed first in the US, is based on a bacteria killing mechanism found in yoghurt.

By using CRISPR technology, scientists could potentially edit cane toad genes to engineer “daughterless” toads, turning the pests all male and destroying populations.

“I think the CRISPR type solution will arrive faster than people think,” Mr Sawyer said.

“We need a harm minimisation strategy, but without a genetic tool, these strategies are localised and restricted.”

Mr Sawyer also watered down any suggestion such technology could pose too much environmental risk.

“I can’t possibly see that this could do damage when you look at the actual damage toads have done,” he said.

“Anything that can take the pressure off our native wildlife from toads would be worth doing.”

Prof Shine’s four-step plan included pheromone-based methods to kill eggs, tasteaversion training of vulnerable predators, exposing toads to a deadly pathogen and quarantining toads away from the Pilbara.

The RSPCA has implored the nation to lay down its arms – namely golf clubs and Dettol – in the toad war.

In its submission to the inquiry, the welfare organisation said the killing of adult toads was “problematic in terms of cost-efficiency, sustainability and humaneness.”