Peptide sequence: PGEPGYMGLP GIQGKKGDKG NQGEKGIQGQ KGENGRQGIP GQQGIQGHHG Sequence homology: Dog: 93%; Horse: 100%; Human: 100%; Pig: 100%. COL17A1 is the alpha chain of type XVII collagen. Unlike most collagens, collagen XVII is a transmembrane protein,