TRNT1 (tRNA nucleotidyl transferase 1) is an essential enzyme that catalyzes the addition of terminal cytosine-cytosine-adenosine (CCA) trinucleotides to mature tRNAs, a modification necessary for aminoacylation 1. This nucleotidyltransferase functions in both nuclear and mitochondrial tRNA maturation pathways 2, with mitochondrial pre-tRNA processing involving coordinated removal of 5' leaders, 3' trailer processing, and 3'-CCA addition by TRNT1 3. Partial loss-of-function TRNT1 mutations cause sideroblastic anemia with B-cell immunodeficiency, periodic fevers, and developmental delay (SIFD), characterized by defects in both mitochondrial and cytosolic metabolism 2. The disease demonstrates significant phenotypic heterogeneity, with additional reported features including growth hormone deficiency, hypoglycemia, renal, cardiac, and sensory organ abnormalities 4. Hypomorphic TRNT1 mutations can also cause isolated retinitis pigmentosa with erythrocytic microcytosis, indicating tissue-specific sensitivity to reduced TRNT1 function 5. Clinically, TNF-α inhibitors such as etanercept have demonstrated efficacy in controlling the autoinflammatory phenotype of TRNT1-related disease over extended follow-up periods 6. Recent evidence suggests TRNT1 dysregulation may also contribute to cancer pathogenesis, with elevated TRNT1 expression observed in multiple cancer types and associations with tumor progression and apoptosis regulation 7.