From this, we found a statistically significant negative correlation between serum Sfrp5 concentration and eGFR (r = -0434, P = 0.001) (Figure 1) and between serum Wnt5a and eGFR (r = -0481, P = 0.001) (Figure 2) in these patients with chronic renal disease, i.e. eGFR decreased with increasing serum concentration of these proteins. Here, SFRP5 is linked to chronic kidney disease.