The presence of coexpression of the basal biomarkers CK5+/p63+ (odds ratio, OR = 34.34), grouped two by two, was associated with the familial breast cancer phenotype, while the absence of coexpression of the basal biomarkers CK5-/p63- and CK5-/p-cadherin- (OR = 0.13) was associated with the sporadic cancer phenotype. The gene discussed is KRT5; the disease is breast cancer.