These new articles provide excellent mini-reviews of the highly complex science of genetics of pain.(September, 2014) .
Harald Breivike from the University of Oslo , Norway writes,
'The voltage gated sodium channels, Nav1.7, that are found in central and peripheral nervous tissues are known to malfunction in the rare but dramatic pain condition erythromelalgia. These patients often end up sitting with their feet in buckets of ice-cold water, from which they obtain relief of red-hot and painful feet (and hands). The collaborating research teams of Ellen Jørum, Oslo, and Martin Schmelz, Mannheim-Heidelberg, as well as researchers from the Karolinska Institute and the R&D-centres of Astra Zeneca in Södertälje and Macclesfield report 22 new mutations in pain-related genes coding for several voltage-gated Na-channels (Nav1.8, NaV1.9, NaV1.6, NaV1.5, NaV2.1, SCN1B, SCN3B), for the transient receptor potential channels ankyrin (TRPA1) and vanilloid (TRPV1), and other pain-related targets, such as nerve growth factor receptor . These mutations were documented in 27 of 48 patients with erythromelalgia. The originally described “gain-of-function”mutation in the NaV1.7-gene was found in only 5 of these 48 patients . The extremely important implications of these findings for pain patients and their health care providers are that they document how apparently minor changes in cell membrane ion channels can result in otherwise inexplicable pain conditions.
Knowing that such mutations do exist, and that there must be more still to discover, this can be a relief for pain-patients and their physicians when faced with difficult to understand pain conditions. We should not jump to the conclusion that “there is something the matter with the mental health” of our patients whose pain we cannot explain, much less treat effectively. They may have an undiscovered mutation of pain-related gene(s).'
Full articles are attached. Highlights include :
- Protein modifying mutations of NaV1.7 in 7/48 patients with erythromelalgia.
- •Unidentified cause in majority of erythromelalgia patients.
- •Rare variants of NaV1.8, NaV1.9, or beta-subunits in eight patients with unclear functional link.
- New mutations found
- 1 in 100 000 thought to have EM
Moderator team welcome your thoughts and comments.201-ExonicmutationsinSCN9ANav1.7ZhangetalSeptember2014.pdf (845 KB) 202-EMdramaticpainofgeneticorigin.pdf (132 KB)