Comparing the gene expression between normal breast epithelial cells and four types of breast cancer cells, it was found that all four different types of breast cancer cells exhibited differential expression of theHERV-K_1q23.3, SLAMF1, HERV-K_22q11.23, IGLL1, HERV-K_9q34.11 and LRRC8A. This evidence concerns the gene SLAMF1 and breast cancer.