We have previously estimated that one in two million people will develop bilateral vestibular schwannomas by chance. We show for the first time molecular proof that a man who developed bilateral vestibular schwannomas aged 52 and 67 years of age had developed these by independent events in the NF2 gene with no evidence of a germline or mosaic NF2 mutation or chromosome 22q linked inherited aetiology. Furthermore we estimate that up to 50% of those presenting with bilateral vestibular schwannomas alone after 70 years of age are likely to have developed these by chance. This research will mean that people developing just vestibular schwannomas on both sides at older ages can be reassured that the risks for their children are likely even lower. (By Prof. D Gareth Evans, http://jmg.bmj.com/content/early/2015/02/27/jmedgenet-2014-102973 )