Anti-amyotrophic lateral sclerosis 2 chromosome region candidate 11 antibodies are used in antigen-specific immunodetection in biological samples. The target amyotrophic lateral sclerosis 2 chromosome region candidate 11 is a known alias name of the protein C2 calcium dependent domain containing 6, encoded by the C2CD6 gene in humans. This 1820-amino acid residue protein is reported to be an auxiliary component of the CatSper complex, a complex involved in sperm cell hyperactivation. It is localized to the cell projections of the cell. In terms of tissue expression, it is notably expressed in the testis.