NRAS gene mutation testing
The RAS family of proteins are encoded by three closely related
genes; HRAS, KRAS, and NRAS. These three genes
are mutated in approximately 20% of human tumours, although
mutations in KRAS account for 85% of these.
While KRAS mutations are common in cancers of the
pancreas, colon and lung, mutations of the NRAS gene occur
more frequently in melanoma and myeloid leukaemias.
Acquired mutations of the NRAS gene are found in
approximately 20% of melanomas. These mutations, all of which
activate their protein product constitutively, occur in codons 12,
13, and 61, those of codon 61 being by far the most frequent.
The cellular consequences of activating mutations of
NRAS are well understood; constitutive activation of the
MAPK and PI3K/AKT pathways leads to melanoma growth and
progression. However; the clinical significance of the presence of
NRAS mutations in melanomas remains unclear.
Source Bioscience now offers testing for NRAS mutations
occurring in codons 12, 13, and 61, using proprietary
pyrosequencing assays. These tests are suitable for FFPE material,
which can be submitted as blocks or sections. All samples are
evaluated for tumour burden prior to testing, and macro-dissection
carried out if required.