A further two Rabs showed strong and specific interactions with membrane traffic machinery that we did not validate because of a lack of suitable reagents: Rab26 with the spastic paraplegia proteins Spg11 and Spg15 (also found with Rab7), and Rab35 with the Rab GEF Sbf (SBF1/2 in humans). The gene discussed is SBF1; the disease is paraplegia.