Using a whole genome and transcriptome amplification and a pan-pathogen microarray (PathoChip) strategy, Banerjee’s research group investigated the diversity of the microbiome in the four major types of breast cancer: endocrine receptor (ER) positive, triple positive, Her2 positive and triple negative breast cancers (Banerjee et al., 2018). This evidence concerns the gene ERBB2 and breast cancer.