AR and Fuchs endothelial corneal dystrophy: Since the first repeat expansion in an exonic CAG repeat in the androgen receptor (AR) gene was characterised as causative for spinal and bulbar muscular atrophy (Kennedy’s disease) in 1991,18 most of the repertoire (current count at around 60 or so) of repeat expansion disorders described to date are associated with neurological or neurodevelopmental disease.19, 21 There are only a handful of non-neurological syndromes associated with repeat expansions including Fuchs endothelial corneal dystrophy,22 synpolydactyly type 123 and hand-foot-genital syndrome.24