ABHD12 and Polyneuropathy - hearing loss - ataxia - retinitis pigmentosa - cataract: Since Abhd12 encodes a serine hydrolase abhydrolase domain-containing protein 12 (or lysophosphatidylserine lipase ABHD12) that catalyzes the hydrolysis of 2-arachidonoyl glycerol (2-AG) to arachidonic acid and glycerol, PHARC syndrome has been classified as both an inborn error of endocannabinoid metabolism and an inborn error of phospholipid metabolism involving elevated levels of lysophosphatidylserine lipids and the endocannabinoid 2-AG (Fiskerstrand et al. 2010; Blankman et al. 2013; Lamari et al. 2013; Wortmann et al. 2015; Leishman et al. 2019).