Anti-FMR1 neighbor antibodies are used in the immunodetection of the protein encoded by the FMR1NB gene. In humans, the canonical protein has a reported length of 255 amino acid residues and a mass of 29.2 kDa. Its subcellular localization is in the membrane. It is reported to have testis-specific expression. Other names for this target antigen include cancer/testis antigen 37, sarcoma antigen NY-SAR-35, and FMR1 neighbor protein.