Australian Scientists Develop Gene Drive to Reduce Feral Rabbit Numbers

Scientists at the University of Melbourne are developing a gene drive to limit the breeding capacity of feral rabbits in Australia. The approach uses IVF and gene-editing to create laboratory-bred rabbits whose female offspring are infertile while males remain fertile.

Dr Ellen Cottingham, a University of Melbourne research fellow, collects tissue samples from rabbits at Mt Rothwell Wildlife Sanctuary west of Melbourne. The samples are processed at the university to identify genes that control fertility in both sexes.

The planned release strategy involves fertile males carrying the gene drive. All of their female offspring would be infertile, causing a population decline that accelerates as the modified gene spreads through breeding. "It's like a selfish gene that spreads really, really fast through a population, and it's spread through breeding much faster than normal DNA inheritance occurs," Dr Cottingham said.

Existing viral controls such as calici and myxoma have lost effectiveness in recent years. Rabbit numbers have reached their highest levels in decades, producing agricultural losses exceeding $200 million annually. Dr Kasia Filimonow from Poland and clinical embryologist Dr Naomi Tappe are assisting with IVF procedures.

In recent days the team has grown rabbit embryos using these methods. Dr Cottingham said the technology could later be adapted for other invasive species including cane toads, European carp, feral cats and foxes. Any release would require consultation with government, landholders and other stakeholders, and is estimated to be at least six years away.