An inborn error of endocannabinoid metabolism has been described in 19 patients (Fiskerstrand et al. 2010, Am J Hum Genet 87:410-7), clinically characterized by polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataracts (PHARC). ABHD12 as an integral membrane protein with an active site located on the extracellular side. The mutated enzyme normally hydrolyzes 2-arachidonoyl glycerol, an endocannabinoid lipid transmitter acting on cannabinoid receptors involved in notably in neurotransmission, pain appreciation, and inflammation.
Philippe Campeau, MD