POLR1E is a core subunit of RNA polymerase I (Pol I), the enzyme responsible for synthesizing ribosomal RNA precursors 1. As a component of the Pol I complex, POLR1E participates in forming the transcription initiation complex at rRNA gene promoters, facilitating interactions between Pol I and the transcription factor UBTF/UBF 1. The protein localizes to the nucleolus and fibrillar center, consistent with its role in coordinating Pol I-dependent rRNA synthesis 2. Disease relevance spans multiple conditions. Truncating POLR1E variants were identified in three independent pedigrees with familial Hodgkin lymphoma, suggesting genetic predisposition to this hematological malignancy 3. POLR1E expression is significantly elevated in multiple sclerosis during acute clinical and radiological relapse (p=0.0001), implicating dysregulated Pol I pathway activity in MS pathogenesis 4. POLR1E expression correlates with increased tumor stage in bladder cancer and represents a potential diagnostic marker 5. Additionally, genome-wide association analysis identified POLR1E variants associated with lamotrigine treatment response in bipolar disorder patients 6. These findings suggest POLR1E dysfunction contributes to oncologic, neurological, and psychiatric disease pathogenesis, positioning the gene as both a biomarker and potential therapeutic target.