To comprehensively assess kidney injury progression, we included not only conventional renal function markers (eGFR, BUN, and CysC), but also a broader range of renal function phenotypes, including indicators related to acute kidney injury (NGAL and KIM-1), markers of glomerular permeability (MAU and UACR), dynamic markers of kidney injury (CKDi25 and Rapid3), stages of kidney injury progression (ARF and CKD), and end-stage renal dialysis status The results revealed a significant positive causal relationship between mtDNA-CN and the continuous variable eGFR (OR = 1.006, p = 0.003). The gene discussed is LCN2; the disease is acute kidney injury.