A decade ago already, three PTPRJ polymorphisms (rs1566734, rs1503185 and rs4752904) were linked to human platelet reactivity and suggested to lower the risk of heparin-induced thrombocytopenia (Rollin et al., 2012) although this could not be confirmed in a French patient cohort (Lioger et al., 2016). The gene discussed is PTPRJ; the disease is Thrombocytopenia.