In 2020 and 2022, it was noted that OAT1 and OAT3 are involved in UA reabsorption and excretion in renal proximal tubules and interact with gut flora metabolites (e.g., indoleacetic acid and 4-hydroxyphenylacetic acid) to affect UA levels, which in turn affects the progression of CKD (Engelhart et al., 2020; Granados et al., 2022; Jamshidi and Nigam, 2022). This evidence concerns the gene SLC22A6 and chronic kidney disease.