Scientists from plant research charity The Sainsbury Laboratory hired games developer Team Cooper to develop Fraxinus, which is played via the social networking site Facebook.
It uses real genetic data from Chalara fraxinea, the fungus which causes ash dieback, and from the common ash (Fraxinus excelsior). The two genomes consist of about 60 million and one billion nucleotides, or "letters", respectively.
Players have to line up coloured leaves which represent sequences of nucleotides from real-world samples against a reference, so identifying possibly useful mutations. Computers are notoriously poor at such pattern-matching.
"Each play of the game will contribute a small but useful analysis," said Dr Dan MacLean from The Sainsbury Laboratory who conceived the idea.
Professor Allan Downie from the John Innes Centre, a partner organisation in the Open Ash Dieback Project, said: "The clues generated by members of the public could help us breed from naturally-resistant individual trees to re-establish our ash woodlands."
The game can accessed from its app page on Facebook.