To obtain similar sized groups for association studies, the 450 breast cancer samples were categorized into two groups: patients with breast tumors with weakly positive Ki-67 staining (<25% Ki-67 positive cells, n = 253, 56.2%) or patients with breast tumors with positive Ki-67 staining (≥25% positive cells, n = 197, 43.8%), similar to cutoff values of ≥20% in previous studies [17], [20], [21]. Here, MKI67 is linked to breast cancer.