How smallest DNA virus evolved in rare parakeets

Scientists have gained new insight into a virus that is threatening to wipe out the Mauritius parakeet.

The Mauritius parakeet was saved from the brink of extinction 30 years ago, thanks to the work of an international team of conservationists, including scientists from Kent. Now an outbreak of deadly Beak and Feather Disease is once again raising the spectre of extinction.

But a team led by Dr Jim Groombridge, of the University’s Durrell Institute of Conservation and Ecology (DICE), has been able to make use of its archive of DNA samples from Mauritius parakeets, built up over many years, to identify how the world’s smallest DNA circoviruses have evolved to cause the spread of the disease.

The team’s findings, published in the Journal of Virology, are exciting for scientists because the gene involved in viral replication, one of only two genes known for this virus, has always been considered to be relatively impervious to the influence of natural selection.

Perhaps most remarkable of all was how the new mutant forms of the virus then quickly out-competed all other viral genotypes within the parakeet population. This phenomenon, known as a selective sweep, has never before been observed in such detail in a virus infecting a natural wildlife population.

Now the team, made up of scientists from DICE, which is part of the University’s School of Anthropology and Conservation, as well as Kent’s School of Mathematics, Statistics and Actuarial Science, Wildlife Vets International, the Mauritius Wildlife Foundation, the Durrell Wildlife Conservation Trust and the Roslin Institute, have focused research on the immune system of the Mauritius parakeet. This will form part of continued international efforts to assist the Mauritius government to save this endangered species.

For more information contact: Katie Newton.