PAR1 may refer to: PAR1 (gene), Prader–Willi/Angelman region-1 gene PAR-1, a serine/threonine-protein kinase of the KIN2/PAR-1/MARK kinase family Coagulation factor II receptor Parchive, a data archive format PAR1, one of the pseudoautosomal regions of the X or Y chromosome