Systemic Sirt7 knockout mice with lower renal K-Cl cotransporter (KCC)4 expression under ammonium chloride stimulation exhibited increased metabolic acidosis, and further studies have revealed that Sirt7 interacts with KCC4 to stabilise and regulate KCC4 activity through deacetylation and delays the exacerbation of renal metabolic acidosis [71]. The gene discussed is SLC12A7; the disease is metabolic acidosis.