AGXT2 is a mitochondrial aminotransferase with broad substrate specificity that catalyzes multiple metabolic transformations. It converts glyoxylate to glycine using alanine as an amino donor, metabolizes D-beta-aminoisobutyric acid, and transfers amino groups from beta-alanine to pyruvate 1. A key physiological function involves catabolism of asymmetric (ADMA) and symmetric (SDMA) dimethylarginines, endogenous inhibitors of nitric oxide synthase; this activity provides a mechanism through which kidneys regulate blood pressure. AGXT2 has emerged as clinically relevant in cardiovascular and neurological contexts 2. Genetic variants in AGXT2—particularly rs37369 and rs16899974—associate with circulating SDMA levels and heart rate variability in young adults, though they do not predict overall mortality in patients undergoing coronary angiography 3. AGXT2 variants in the AGXT2 region also associate with mild cognitive impairment in Hispanic/Latino, African American, and European American populations, with evidence suggesting mediation through beta-aminoisobutyric acid (BAIBA) metabolism 4. While AGXT2 can metabolize beta-alanine in vitro, its in vivo importance for beta-alanine homeostasis appears modest 5. Recent evidence indicates AGXT2 may function primarily as a back-up enzyme in ADMA metabolism under pathophysiological conditions rather than as the major regulator of blood methylarginine levels 6.