ZFHX3 and spinocerebellar ataxia type 4: These are: (1) the well-known polyglutamine repeats from exonic CAG repeat expansion; (2) polyalanine repeat expansion disorders associated with congenital malformation syndromes with the exception of the PABPN1 GCN repeat expansion associated with OPMD (where N could be an A/T/C/G nucleotide)31 and (3) the new disease entity of polyglycine disorders identified after the discovery of an exonic GGC repeat expansion in ZFHX3 associated with SCA4.32, 35