Interleukin-6 gene polymorphisms correlate with the progression of nephropathy in Chinese patients with type 2 diabetes: A prospective cohort study.

•Interleukin-6 (IL-6) serves a candidate gene involved in susceptibility to nephropathy.•This longitudinal study focused on 568 type 2 diabetes patients with normoalbuminuria.•Development of diabetic nephropathy over 5.3years was examined.•IL-6 polymorphisms is associated with progression of nephropathy in diabetic patients.