Number of unique ligands per receptor class

Class (Family)	A (Rhodopsin)	B1 (Secretin)	B2 (Adhesion)	C (Glutamate)	D1 (Ste2-like fungal pheromone)	F (Frizzled)	T2 (Taste 2)	Total
No. ligands	190,799	5,832	0	8,066	0	972	466	206,135
Average no. ligands/GPCR	651	389	0	367	0	88	19	411
No. GPCRs with ligand (%)	209 (71)	14 (93)	0 (0)	11 (50)	0 (0)	4 (36)	25 (100)	263 (52)

Specific sets of ligands can be downloaded from the ligand browser.

Ligand coverage of GPCR Classes

Circle colors indicate a number of ligands:

< 100

< 500

< 1000

1000+