Biological marker or biomarker is an indicator of physiological or pathological changes in an organism. A biomarker is valid only after evaluation and approval by Food and Drug Administration (FDA) committee. Three step evaluation processes for biomarker includes: Validation, Qualification and Utilization. Present review highlights recent trends of biomarker in Diabetes and diabetic nephropathy and an emerging protein a natural boon for life: the Sirtuin. Sirtuin a diverse ancient protein family has its role as a biomarker as well as a metabolite essential for day to day wear and tear of cells in the system of an organism. It is an NAD- dependent class III histone deacetylase and mono ADP- ribosyl transferase enzyme. Sirtuin is a seven member family from sirtuin 1 to 7 (Sirt1- 7) based on their function, composition and localization. Sirt1 is the closest homologue of Sir2 of yeast and with wide range of functions. Hence sirtuin is a molecule of interest for research. Isoforms are localized in nucleus, mitochondria and cytoplasm for respective metabolic functions in the cell
