It is known that SETD3 regulates the expression of genes related to normal physiology, development and cancer progression such as FOXM1 (Forkhead Box M1), ACTB (β-actin), ASMA (alpha-smooth muscle actin), ACTG (λ-actin), FSCN (Fascin Actin-Bundling Protein), FBXW7 (F-Box and WD Repeat Domain Containing 7)10,22,29–32 but it is not yet known whether this regulation also occurs in breast cancer. The gene discussed is ACTG1; the disease is breast cancer.