The Fkbp5/FKBP5 genotype in rodents and humans, respectively, has been associated with differences in stress reactivity and alcohol withdrawal [9, 24–26]. A functional polymorphism in the human FKBP5 gene has been identified, SNP rs1360780; homozygosity for the minor allele T has been associated with twice the amount of FKBP5 protein levels in lymphocytes, relative to the other genotypes [27]. Furthermore, differential stress responsivity, distinctive Amy overreactivity to emotional stimuli as well as psychiatric phenotypes characterized by an impaired stress response have been associated with the T allele or TT genotype, alone or in interaction with aversive environmental factors [9, 28].
