In summary, this series of experiments suggested that the TCF7L2 transcript variant “T-3”, which is highly expressed in the human brain but not in the other tissues that we tested, might be linked to the BD-BMI risk SNP rs12772424 through GR signaling—a possibility supported by the fact that the rs12772424 SNP creates a GRE. The gene discussed is TCF7L2; the disease is Behcet disease.