In rhesus macaques, SNP 77C>G (Pro26Arg) in the N-terminal appears to be functionally equivalent to the human 118A>G. Carriers of the 77G variant showed increased psychomotor stimulation in response to alcohol, increased frequency of alcohol consumption to intoxication, increase of alcohol preference following naltrexone treatment, altered stress reactivity, reduced cortisol response to maternal separation in infancy and to acute alcohol exposure later in life and attenuated cortisol levels during the maternal postpartum period (Barr et al. 2010; Barr et al. 2007; Miller et al. 2004; Schwandt et al. 2011; Vallender et al. 2010).
