Increased expression of genes that confer favorable breast cancer outcomes (Klf6, Klf9, Nid2, Ntn4, Per1, and Txnip) and decreased expression of those associated with aggressive disease (Bcar3, Cldn12, Csf1, Jag1, Lgals3, Lypd3, Nme1, Ptges2, Ptgs1, and Smarcb1) in choline supplemented group. This evidence concerns the gene PER1 and breast cancer.