Because the c-mpl gene was considered as one of the candidate genes for this disorder, we analyzed the genomic sequence of the c-mpl gene of a 10-year-old Japanese girl with CAMT.
Here, we report for the first time two different MPL amino-acid substitutions in a 2-year-old Italian boy with CAMT and compound heterozygosis for two (c-mpl point mutations.
Recently, two heterozygous truncating mutations of the thrombopoietin (TPO) receptor MPL, coded by the c-mpl gene, were identified in a 10-year-old Japanese patient with CAMT transmitted in an autosomal recessive manner.
Mutations in the genes of hematopoietic growth factor receptors as a cause of congenital cytopenia, such as congenital amegakaryocytic thrombocytopenia (CAMT) or severe congenital neutropenia (CN), are discussed.
Three parameters, plasma thrombopoietin levels, plasma glycocalicin levels and megakaryocyte culture, distinguish between different causes of congenital thrombocytopenia.
Recently, we and others could define the molecular cause of the rare disease congenital amegakaryocytic thrombocytopenia (CAMT) as mutations in the c-mpl gene (Blood 97: 139, 2001).
Thrombopoietin is essential for the maintenance of normal hematopoiesis in humans: development of aplastic anemia in patients with congenital amegakaryocytic thrombocytopenia.
Using in vitro assays with hematopoietic progenitors from patients of both patient groups we could provide experimental evidence for a residual activity of the thrombopoietin receptor in CAMT II patients.
Using in vitro assays with hematopoietic progenitors from patients of both patient groups we could provide experimental evidence for a residual activity of the thrombopoietin receptor in CAMT II patients.
Using in vitro assays with hematopoietic progenitors from patients of both patient groups we could provide experimental evidence for a residual activity of the thrombopoietin receptor in CAMT II patients.
Using in vitro assays with hematopoietic progenitors from patients of both patient groups we could provide experimental evidence for a residual activity of the thrombopoietin receptor in CAMT II patients.
Previously, we identified an inherited syndrome of congenital amegakaryocytic thrombocytopenia and radio-ulnar synostosis that is associated with a point mutation in the third helix of HOXA11 homeodomain (HOXA11-DeltaH3).
Congenital amegakaryocytic thrombocytopenia (CAMT) and thrombocytopenia with absent radii (TAR) share features of isolated thrombocytopenia, reduced or absent marrow megakaryocytes, impaired responsiveness to thrombopoietin (TPO), and high plasma TPO levels.