It emerged that (i) CK7 was more frequently expressed by CrD-SBC mucosae in comparison with no-PID-SBC mucosa (p<0.001) and (ii) a highly significant (p<0.001) association existed between CK7 expression by CrD-SBCs and their respective mucosae, while such an association was lacking among no-PID-SBC cases. The gene discussed is KRT7; the disease is pelvic inflammatory disease.