Composition and functional potential of the mammary microbiota prior to and following breast tumor diagnosis

These data were generated to analyze the human breast tissue microbiome composition and functional potential. We analyzed and compared the resident bacterial taxa of histologically normal breast tissue (healthy, H) with those of tissues donated prior to (pre-diagnostic, PD, ) and after (adjacent normal, AN, and tumor, T) breast cancer diagnosis to determine the role of the breast tissue microbiome in breast cancer. DNA was isolated from 165 tissue samples, 9 negative controls, and 1 positive control and submitted for Illumina Miseq paired-end sequencing of the V3 - V4 region of the 16S gene. 16S amplicons were pre-processed into amplicon sequence variants (ASVs) using DADA2. To infer bacterial function in breast cancer, we predicted the functional bacteriome from these ASVs using PICRUSt2 and the Kyoto Encyclopedia of Genes and Genomes (KEGG) database.