EPM2AIP1 (EPM2A interacting protein 1) is a protein-binding partner located on chromosome 3.1 that interacts with laforin, the product of the EPM2A gene mutated in Lafora disease, a severe form of progressive myoclonus epilepsy 1. The two proteins show subcellular colocalization and are ubiquitously expressed 1. EPM2AIP1 shares a common promoter with MLH1, making it a potential biomarker for MLH1 promoter methylation status 2. In endometrial cancer, EPM2AIP1 immunohistochemistry demonstrates high concordance with MLH1 methylation (95% accuracy, 94.5% sensitivity, 98.1% positive predictive value), showing promise as a surrogate marker for methylation testing 2. However, EPM2AIP1 IHC shows limited utility in colorectal cancer, with only 64% sensitivity and 67% specificity for detecting MLH1 promoter hypermethylation 3. Emerging evidence identifies EPM2AIP1 methylation probes as part of an optimal feature subset for MSI detection through deep learning approaches, associating with improved tumor immunotherapy characteristics 4. Additionally, EPM2AIP1 has been identified as a hub gene dysregulated in type 1 diabetes, suggesting potential involvement in autoimmune pathways 5. Its exact molecular function remains incompletely characterized 1.