FAAH2 and psychiatric disorder: The hemizygous variant located on the X-chromosome affecting FAAH2 (hg19: g.57475100G > T) was considered a very strong candidate in that it harbored a missense mutation c.1372G > T (p.Ala458Ser), FAAH2 is known to play a role in lipid metabolism [21] and alterations in endocannabinoid metabolism have been documented in many different psychiatric disorders [6].