Association of Fetuin-A with Thr256Ser exon polymorphism of α2-Heremans Schmid Glycoprotein (AHSG) gene in type 2 diabetic patients with overt nephropathy

Circulatory Fetuin-A has been well reported to elevate the risk for Diabetic Nephropathy (DN) and is associated with many vascular complications. Compelling reports have well documented that the circulatory levels of Fetuin-A directly have an impact on its AHSG (α2- Heremans- Schmid Glycoprotein) gene single nucleotide polymorphisms (SNP). Thus, in this study among the South Indian T2DM population, we aim to explore the association of AHSG Thr256Ser (rs4918) SNP in subjects with DN and correlate with the circulatory levels of Fetuin-A at various stages of DN patients. A total of 975 subjects were recruited, such as Group-I, consisting of Controls (n = 300), Group-II, with normoalbuminuria (n = 300), Group-IIIa, with incipient microalbuminuria (n = 195), Group-IIIb, with persistent macroalbuminuria (n = 180)] and were subjected for genotyping using PCR-Restriction Fragment Length Polymorphism (RFLP). Circulatory Fetuin-A was measured using sandwich enzyme-linked immunosorbent assay (ELISA). The ‘G’ allele of AHSG exon-7 (C/G) SNP is significantly concomitant and conferred significant risk for normoalbuminuria subjects. In the DN subjects, the ‘G' allele showed the risk for persistent macroalbuminuria. A noticeable stepwise decrease was evidenced in the circulatory Fetuin-A among persistent macroalbuminuria over incipient microalbuminuria from normoalbuminuria. Further, the circulatory Fetuin-A was lowered in DN subjects with mutant GG genotype than the wild CC. AHSG Thr256Ser (rs4918) SNP was associated with renal complications among South Indian T2DM subjects. •The association of AHSG Thr256Ser (rs4918) SNP in subjects with DN•Correlation of circulatory Fetuin-A at various stages of DN patients.•The circulatory Fetuin-A was found to be lowered in DN subjects with mutant GG genotype than the wild CC.•AHSG Thr256Ser (rs4918) SNP is associated with renal complications among South Indian T2DM subjects