SELENOP and breast cancer: Despite apparent differences between SNP associations and breast cancer risk among different NA ancestry groups, only SEPN1 rs718391 (p=0.03 padj =0.10), SEPP1 rs230812 (p=0.005, padj = 0.008), and SEPP1 rs6865453 (p=<0.001, padj = 0.002) showed significant interaction by ancestry.