MRPL38 and Alzheimer disease: Conversely, genetically predicted increased expression of PGS1 (OR: 0.931; 95% CI: 0.868–0.998; p = 0.045), ETFA (OR: 0.965; 95% CI: 0.933–0.998; p = 0.038), and MRPL38 (OR: 0.927; 95% CI: 0.867–0.992; p = 0.029) was associated with reduced AD risk, suggesting protective effects through roles in cardiolipin synthesis, electron transfer, and mitochondrial ribosomal function in mitigating cognitive decline.