Altogether, the RNA-seq data analysis newly demonstrated: (i) the existence of the exon 4-skipping variant of the ZNF217 oncogene in primary breast cancers, expressed at weaker mRNA levels than those of ZNF217-WT; (ii) correlated mRNA expression levels of ZNF217-ΔE4 and ZNF217-WT isoforms in primary breast tumor. Here, ZNF217 is linked to breast cancer.