D1 PER3 differential co-expression between healthy mammary tissues and basal breast cancers yielded five hundred and twenty-one differentially co-expressed genes with PER3. In this case, however, functional categories related to the ATP synthesis through the TCA cycle were not found to be enriched whereas light enrichment in some gene ontology gene sets related to lipid metabolism were found (p-adj = 4.035 × 10−2). This evidence concerns the gene PER3 and breast cancer.