Retraction to: Nature online 14 June 2017

In follow-up experiments to this Letter, we have been unable to replicate key aspects of the original results. Most importantly, the findings from behaviour studies and sequencing of microglia isolated from 564Igi autoimmune mice as shown in Figs. 1a, b, d and 3a, b are not substantiated upon further analysis of the original data. The authors therefore wish to retract the Letter. We deeply regret this error and apologize to our scientific colleagues.