Another patient with stroke and a pulmonary embolism was heterozygous for the p.Pro106Leu variant of the MPL gene, which has been associated with thrombocytosis.
We assume that p.Pro106Leu is a frequent MPL mutation in the Arab population, leading to severe thrombocytosis in homozygotes and occasionally to mild thrombocytosis in heterozygotes.
K39N represents an identified functional Mpl polymorphism and is associated with altered protein expression of Mpl and a clinical phenotype of thrombocytosis.
The thrombopoietin receptor (MPL) has been shown to be mutated (MPL W515L) in myelofibrosis and thrombocytosis yet new approaches to treat this disorder are still required.