Latrophilins (LPHNs) are adhesion G protein-coupled receptors (adhesion GPCRs), the second largest class of GPCRs (Sudhof, 2001). LPHNs consists of three isoforms, LPHN1-3, expressed largely in the CNS (Ichtchenko et al., 1999). Common variants of the LPHN3 gene confer susceptibility to attention-deficit hyperactivity disorder (ADHD) (Arcos-Burgos et al., 2010), predict effectiveness of stimulant medication (Labbe et al., 2012) and impact behavioral and neurophysiological measures of cognitive response control (Fallgatter et al., 2013). A single point mutation in human LPHN3 was found in an ADHD patient (Domene et al., 2011). The mutation is in the olfactomedin domain (Ala247Ser, corresponding to mouse Ala313Ser) but the biological effects of this mutation are currently unknown.
