Anti-KRTAP1-3 antibodies are used in the immunodetection of the protein keratin associated protein 1-3. In humans, the canonical protein has a reported length of 167 amino acid residues and a mass of 17.1 kDa. It is reported to be expressed in the middle/upper portions of the hair cortex, in the region termed the keratogenous zone. It is a member of the KRTAP type 1 protein family. Synonyms for this target antigen include keratin-associated protein 1.8, keratin-associated protein 1.9, and keratin associated protein 1.6.