Application of GAD67 and epigenetic mark thereof which serve as early marker of fetal-original bipolar affective disorder susceptibility

The invention discloses application of GAD67 and an epigenetic mark thereof which serve as early markers of fetal-original bipolar affective disorder susceptibility, and belongs to the field of gene functions and application. Research results show that in hippocampi and white blood cells of fetal rats in a pregnancy ethanol exposure group, compared with a normal control group, the methylation level of a GAD67 promoter region is significantly reduced, and the gene expression of the GAD67 promoter region is improved; after growing up, the rats in the xenobiotic exposure group show high hypothalamic-pituitary-adrenal (HPA) axis stress sensibility and bipolar affective disorder susceptibility under the condition of chronic unpredictable stress. Therefore, risks that offspring have bipolar affective disorder after growing up can be judged by detecting the epigenetic modification and expression levels of the GAD67 genes in the white blood cells of fetal blood/umbilical cord blood. Research bases are provided for an