Based on both sequence homology and function, they have been subdivided into at least six families: Ras, Rho, Rab, Arf, sar1 and Ran, which have complicated and important function.

• 根据其一级结构的同源性及功能将它们分为Ras,Rho,Rab,Arf,sar1和Ran六个家族，具有复杂且重要的生物学功能。