Recent human studies found that (1) IL-18R gene expression is differentially associated with distinct PTSD subtypes [69], (2) a single nucleotide polymorphism (SNP) in the IL-18 gene (rs1946518) is associated with AUD in a highly traumatized civilian cohort comorbid for PTSD [70], and (3) this same SNP is also associated with increased IL-18 expression and greater amygdala reactivity in anxiety [71,72]. This evidence concerns the gene IL18R1 and post-traumatic stress disorder.