Järvinen et al (8) detected 55 cases of ERβ expression out of 92 cases (59.8%) of breast cancer; Mann et al (9) detected 78 cases (66%) out of 118 cases of breast cancer; Fuqua et al (10) detected 184 cases (76%) out of 242 cases; Han et al (11) detected 66 cases (42.6%) out of 155 cases. The gene discussed is ESR2; the disease is breast cancer.