Immunogen sequence: HLTRVTPMGG GCLAQARATL PLCRGSVASA SFPVSPLCPQ EVPEAKGKPV KAAPVRSSTW GTVKDSLKAL SSCVCGQ Highest antigen sequence identity to the following orthologs: Mouse - 42%, Rat - 30%. The estrogen receptor-related factor (ERRF) is a recently ident