MPIG6B and Macrothrombocytopenia: Importantly, null and loss-of-function mutations in human G6b-B have been reported to recapitulate key features of the Mpig6b KO and loss-of-function mouse phenotypes, including a severe macrothrombocytopenia, MK clusters in the bone marrow and myelofibrosis (Hofmann et al., 2018; Melhem et al., 2016).