Selfish genes causing fungal fratricide

Photographer: Raquel Pereira. Image from Uppsala University. 

Selfish genes, genes that are passed on through generations without any benefit to the individual, are thought to be an important driver of evolution. With support from the National Genomics Infrastructure at SciLifelab, researchers at Uppsala University have sequenced two selfish genes found in the fungus Neurospora intermedia, both of which cause fungal spores to kill their siblings. The results, published in Nature Communications, show the two genes aren’t related and thus, may be more common than anticipated.

Selfish genes are genes that are passed on to the next generation without any benefit to the individual, and may sometimes be harmful. One example of selfish genes is ‘spore killers’ which have been found in fungi. If a fungal spore carries the selfish gene, the spore will kill all related (‘sibling’) spores not carrying it, enabling the gene to be passed on. Selfish genes are believed to be important explanatory factors of evolutionary patterns and could be used as pesticides, for an example by inserting them into malaria-bearing mosquitos to reduce their population size. However, the knowledge of selfish genes and how they spread in nature is limited.

Using the SciLifeLab National Genomics Infrastructure, a team of researchers lead by Hanna Johannesson (Uppsala University) at Uppsala University has sequenced genomes from two different kinds of spore killers found in the fungus Neurospora intermedia. Among other things, the results showed that the two spore killers weren’t related and used different genes to kill the sibling spores. Hence, selfish genes may be more common than previously thought.

Read full press release from Uppsala University and full scientific paper in Nature Communications.