Anti-FAM209A antibodies are used in the immunodetection of the protein family with sequence similarity 209 member A. In humans, the canonical protein has a reported length of 171 amino acid residues and a mass of 19.6 kDa. Its subcellular localization is in the nucleus. A member of the FAM209 protein family, FAM209A is believed to play a role in sperm acrosome biogenesis. Synonyms for this target antigen include protein FAM209A and uncharacterized protein C20orf106.