title: Deep sequencing reveals double mutations in cis of MPL exon 10 in myeloproliferative neoplasms.
abstract: Somatic mutations of MPL exon 10, mainly involving a W515 substitution, have been described in JAK2 (V617F)-negative patients with essential thrombocythemia and primary myelofibrosis. We used direct sequencing and high-resolution melt analysis to identify mutations of MPL exon 10 in 570 patients with myeloproliferative neoplasms, and allele specific PCR and deep sequencing to further characterize a subset of mutated patients. Somatic mutations were detected in 33 of 221 patients (15%) with JAK2 (V617F)-negative essential thrombocythemia or primary myelofibrosis. Only one patient with essential thrombocythemia carried both JAK2 (V617F) and MPL (W515L). High-resolution melt analysis identified abnormal patterns in all the MPL mutated cases, while direct sequencing did not detect the mutant MPL in one fifth of them. In 3 cases carrying double MPL mutations, deep sequencing analysis showed identical load and location in cis of the paired lesions, indicating their simultaneous occurrence on the same chromosome.
authors.affiliation: Department of Hematology Oncology, Fondazione IRCCS Policlinico San Matteo, 27100 Pavia, Italy. d.pietra@smatteo.pv.it
authors.forename: Daniela
authors.initials: D
authors.lastname: Pietra
authors.forename: Angela
authors.initials: A
authors.lastname: Brisci
authors.forename: Elisa
authors.initials: E
authors.lastname: Rumi
authors.forename: Sabrina
authors.initials: S
authors.lastname: Boggi
authors.forename: Chiara
authors.initials: C
authors.lastname: Elena
authors.forename: Alessandro
authors.initials: A
authors.lastname: Pietrelli
authors.forename: Roberta
authors.initials: R
authors.lastname: Bordoni
authors.forename: Maurizio
authors.initials: M
authors.lastname: Ferrari
authors.forename: Francesco
authors.initials: F
authors.lastname: Passamonti
authors.forename: Gianluca
authors.initials: G
authors.lastname: De Bellis
authors.forename: Laura
authors.initials: L
authors.lastname: Cremonesi
authors.forename: Mario
authors.initials: M
authors.lastname: Cazzola
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001483:Base Sequence; D005091:Exons / Q000235:genetics*; D005260:Female; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D053614:Janus Kinase 2 / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009196:Myeloproliferative Disorders / Q000235:genetics*; D053628:Receptors, Thrombopoietin / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D053628:Receptors, Thrombopoietin; C082218:MPL protein, human; D053614:Janus Kinase 2