In our previous studies using two di-peptylpeptidase inhibitors (DPP4i) such as saxagliptin and linagliptin in type 2 diabetes mellitus (T2DM) patients [43, 44] we have demonstrated that CD34+ve cells are responsive to a change in therapy or intervention within 2–4 weeks using CD34+ as a biomarker and CD34+ cell based assays can be used as a reliable non serum based cellular bio-marker. The gene discussed is CD34; the disease is type 2 diabetes mellitus.