MYH6 and ventricular septal defect: The two variants, g.4085G>C (rs1222539675) and g.4716G>A (rs377648095) found in VSD patients, significantly reduced the gene promoter expression activity and decreased luciferase expression compared to the wild-type MYH6 gene promoter (p < 0.001) in HEK-293 (Fig. 3A) and HL-1 cells (Fig. 3B).