Immunogen sequence: SQASGITGSY SVSESPFFSP IHLHSNVAWT VEDPVDSAPP GQRKKEQWYA GINPSDGINS EVLEAIRVTR HKNAMAERWE SRIYASEEDD Highest antigen sequence identity to the following orthologs: Mouse - 70%, Rat - 73%. The exact function of C19orf21 remains unknown.