RAMP3 and post-traumatic stress disorder: The second GWS CpG site associated with current PTSD included cg03284870, which is located in RAMP3, a gene involved in GPCR signaling; and the third, cg22500183, maps to the AP2B1 gene, which encodes the adaptor protein complex 2, which is implicated in synaptic vesicle pathway, axonal guidance, and immune function.