The most significant alterations observed in fibromyalgia involve dysfunctions in monoaminergic neurotransmission, leading to elevated levels of excitatory neurotransmitters such as substance P [39,40] and glutamate [41], as well as decreased levels of serotonin and norepinephrine in the spinal cord at the level of descending antinociceptive pathways. The gene discussed is TAC1; the disease is fibromyalgia.