In the literature, methylation analyses were performed using genes encoding proteins, such as BDNF, FKBP5, IL-18, MAN2C1, NR3C1, SKA2, SLC6A4 and TLR8, which play a role in the synaptic plasticity, immune system, serotonin modulation, neurogenesis, and inflammation response in PTSD.3, 73While clinical researches are vital in the administration of new therapeutic agents to people with PTSD, animal models are indispensable for comparing the behavioral and physiological effects caused by trauma, as well as molecular and biochemical abnormalities and the state of homeostasis. The gene discussed is SLC6A4; the disease is post-traumatic stress disorder.