Also, our micro-interpretation identified the comorbidity mechanism through hypothalamic pituitary adrenal axis (HPA axis) and Brain derived neurotrophic factor (BDNF) and integrated treatment strategy of depression and T2DM.<h4>Conclusion</h4>The results of the study outlined the evolving knowledge and research focus in this field. The gene discussed is BDNF; the disease is type 2 diabetes mellitus.