PNPLA2 and breast cancer: Subsequent MR analysis revealed key genes potentially associated with breast cancer, culminating in the identification of 12 co-expressed genes, encompassing seven upregulated genes (OLR1, ADIPOR1, CEACAM6, DNASE2, CD53, BMF, and CAMP) and five downregulated genes (PIK3R1, PNPLA2, ATOH8, TTC23, and CWF19L2).