NPM1 exon 12 Variants

Disease-causing variants in exon 12 of the nucleophosmin (NPM1) gene have been reported to be AML specific and result in an accumulation of nucleophosmin (NPM) protein in the cytoplasm, other human neoplasms consistently show nucleus-restricted NPM expression (Falini et al. (2005) NEJM 352 (3) 254-266 and Falini et al. (2007) Blood 109 (3) 874-885). Due to the accumulation of NPM protein in the cytoplasm this subgroup of AML has been termed NPMc+ AML. NPM1 exon 12 variant analysis can therefore be used as a tool in the differential diagnosis of NPMc+ AML. However, the use of this variant for diagnostic purposes MUST be interpreted in combination with clinical and morphologic features.

NPM1 exon 12 variants are detected using fragment analysis in conjunction with capillary electrophoresis.

All samples must be accompanied by a Molecular Haemato-Oncology Request Form which can be completed electronically, printed and sent with each sample.


Laboratory contact: Dr Caroline Wickham 01392 408252

Clinical contact: Dr Paul Kerr 01392 402917


The laboratory participates in the UK NEQAS LI NPM1 Mutation Detection EQA scheme.