From analysis of naturally occurring pVHL mutants, it seems that only point mutations such as pVHL(Y98H) and pVHL(Y112H) (that predispose to haemangioblastoma and phaeochromocytoma, but not to renal cell carcinoma) disrupt pVHL's microtubule-stabilizing function.
Another mutation, T547C, which causes Tyr112 to His, has been seen at the same position and has been associated with VHL type 2A (pheochromocytoma, but no renal cell carcinoma) in two families with a total of 22 affected individuals [Chen F, Slife L, Kishida T, Mulvihill J, Tisherman SE, Zbar B, 1996: J Med Genet 33:716-717].