MRPS30 (mitochondrial ribosomal protein S30) is a structural component of the mitochondrial ribosome that functions in mitochondrial protein synthesis 1. The protein plays a key role in apoptosis and is involved in maintaining mitochondrial homeostasis 12. MRPS30 expression is regulated by genetic variants, with the 5p12 breast cancer susceptibility locus affecting its expression specifically in estrogen receptor-positive tumors through chr5 remodeling mechanisms 31. The gene demonstrates disease relevance across multiple conditions: it is significantly overexpressed in breast cancer tissues and cell lines 4, serves as a biomarker in Alzheimer's disease where decreased expression correlates with mitochondrial dysfunction 5, and contributes to depression pathophysiology through mitochondrial mechanisms 2. Clinically, MRPS30 has emerged as a prognostic marker in multiple myeloma, where it is part of an exosome-related gene signature associated with immune microenvironment modulation and treatment resistance 6. The protein's dual role in mitochondrial function and apoptosis regulation makes it a potential therapeutic target across various malignancies and neurodegenerative disorders.