GPHN and cerebellar ataxia: All 106 serum and 61 CSF samples were examined by immunofluorescence with live rat hippocampal neurons (sera from cerebellar ataxia and stiff-person syndrome cases where also tested in cultures of cerebellar neurons), HEK293 cells expressing α1/β3 subunits of GABAaR, α1 subunit of GlyR, gephyrin or GABARAP.