Three groups were formed based on the EGFR value: stage 1 (S1), with EGFR > 90 mL/min/1.73 m2 which refers to asymptomatic CKD; stage 2 (S2), with EGFR between 60 and 90 mL/min/1.73 m2 which indicates mildly reduced kidney function, and stage 3 (S3) with EGFR < 60 mL/min/1.73 m2 which suggest moderate and severe CKD [17]. This evidence concerns the gene EGFR and chronic kidney disease.