In addition, and surprisingly, the SNPs in ZNF423 displayed SERM and SNP-dependent “reversal” of the E2 induction of both ZNF423 and BRCA1—with induction of expression in subjects with variant SNP genotypes during SERM exposure that was associated with decreased breast cancer risk, and the opposite effect in subjects with a “wild type” (WT) SNP genotype for rs9940645, a SNP that mapped 200 bp distant from an estrogen response element ﻿(ERE). This evidence concerns the gene ZNF423 and breast cancer.