Although numerous classification schemes have been proposed, the superfamily was classically divided into three main classes (A, B, and C) with no detectable shared sequence homology between classes.
Meskipun banyak skema klasifikasi telah diusulkan, superfamili secara klasik dibagi menjadi tiga kelas utama (A, B, dan C) tanpa adanya kesamaan homologi urutan antar kelas.