The human Bestrophin family has four members, Best1, Best2, Best3 and Best4. These transmembrane proteins can function as chloride channels, and can also regulate calcium channels (1). The Bestrophins all have a conserved domain which begins at the N-terminus and is predicted to contain four transmembrane regions; the highly variable cytosolic domain, which follows the fourth transmembrane region, distinguishes the family members from one another (2).
