PDGFB and bilateral striopallidodentate calcinosis: Similarly, several functional studies subsequently demonstrated that PDGFR-β autophosphorylation, in response to PDGF-BB (the dimer of PDGF-B) stimulation, is abolished/reduced due to PDGFB or PDGFRB mutations [99–101], indicating that a functional loss of PDGF-B/PDGFR-β may be the cause of PFBC.