MYELOPROLIFERATIVE DISORDERS (MPD): MPL EXON 10 VARIANTS

MPL exon 10 p.(Trp515Leu) and p.(Trp515Lys) variants have been reported in 13.2% of cases of primary myelofibrosis in which no JAK2 p.(Val617Phe) variant was detected and 7.1% of cases of essential thrombocythaemia in which no JAK2 p.(Val617Phe) variant was detected. MPL exon 10 p.(Trp515Leu) and p.(Trp515Lys) variants were not detected in patients with polycythaemia vera (Schnittger et al. 2012 haematologica 97 (10) 1582-1585).

MPL exon 10 p.(Trp515Leu) and p.(Trp515Lys) variants are identified by Real-Time PCR using the MPL MutascreenTM Kit (Ipsogen) which can detect the MPL p.(Trp515Lys) and p.(Trp515Leu) variants when present at a level of greater than approximately 5% in a background of genomic DNA. This assay cannot be used for the detection of other, less common, MPL variants, for example p.(Trp515Arg), p.(Trp515Ala) and p.(Ser505Asn).

To request MPL exon 10 p.(Trp515Leu) and p.(Trp515Lys) variant analysis on a stored DNA sample please complete the online Molecular Haemato-Oncology Request Form and email to the Department of Molecular Genetics rde-tr.moleculargeneticsadmin@nhs.net.

Laboratory contact: Dr. Caroline Wickham 01392 408248 caroline.wickham@nhs.net

Clinical contact: Dr. Paul Kerr 01392 402917 paul.kerr1@nhs.net