About 1 out of 10 cases of ALS appear to be linked to repeat expansions in the C9orf72 gene, the most common form of the disease identified to date. 

Researchers are working hard to how these repeat sequences may contribute to ALS in hopes to create a treatment for people with C9 ALS.  And, develop tools to anticipate their needs.

A genetic test is now available - enabling clinicians to confirm the diagnosis. Cutting-edge imaging techniques are beginning to emerge - paving the way to predicting outcomes. And, the first potential treatment strategy, developed in partnership with ISIS pharmaceuticals, entered the pipeline.

Ahead of the 2014 meeting of the American Academy of Neurology (AAN), ALS Today takes a look back at key advances in C9 ALS in this interactive timeline. Click on the timeline to learn more about emerging strategies to diagnose, track and treat this form of the disease.

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To learn more about C9orf72 ALS, check out ALS on cloud C9. To find out more about emerging treatment strategies for the disease, check out  ALS Antisense and Sensibility.

Image credits: Mark Lythgoe PhD & Chloe Hutton PhD, Wellcome Images; Jonathan Charles, Flickr; George Shuklin, Wikimedia Commons;  Judith Stoffer, National Institute of Genome Sciences; Stephen Neidle PhD, American Chemical Society; European Journal of Human Genetics, Nature Publishing Group; Nature Chemical Biology, Nature Publishing Group and Despicable Me 2 (Viva Press).

References

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Haeusler, A.R. et al. (2014) C9orf72 nucleotide repeat structures initiate molecular cascades of disease.  Nature 507(7491), 195-200. Abstract  |  Full Text  (Subscription Required)

van Blitterswijk, M. et al. (2014) TMEM106B protects C9ORF72 expansion carriers against frontotemporal dementia.  Acta Neuropathologica 127(3), 397-406.  Abstract  |  Full Text (Subscription Required)

Gallagher, M.D. et al. (2014) TMEM106B is a genetic modifier of frontotemporal lobar degeneration with C9orf72 hexanucleotide repeat expansions. Acta Neuropathologica 127(3), 407-418.  Abstract  |  Full Text (Subscription Required)

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Panda, S.K., Wefers, B., Ortiz, O., Floss, T., Schmid, B., Haass, C., Wurst, W. and Kühn, R. (2013) Highly efficient targeted mutagenesis in mice using TALENs. Genetics 195(3), 703-713.  Abstract  | Full Text (Subscription Required)

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Bede, P., Bokde, A.L., Byrne, S., Elamin, M., McLaughlin, R.L., Kenna, K., Fagan, A.J., Pender, N., Bradley, D.G. and Hardiman, O. (2013)  Multiparametric MRI study of ALS stratified for the C9orf72 genotype. Neurology 81(4), 361-369. Abstract  |  Full Text  (Subscription Required)

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Mori, K. et al. (2013) hnRNP A3 binds to GGGGCC repeats and is a constituent of p62-positive/TDP43-negative inclusions in the hippocampus of patients with C9orf72 mutations.Acta Neuropathologica 125(3), 1178-1186. Abstract  |Full Text (Subscription Required)

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Reddy, K., Zamiri, B., Stanley, S.Y., Macgregor, R.B. Jr and Pearson, C.E. (2013) The disease-associated r(GGGGCC)n repeat from the C9orf72 gene forms tract length-dependent uni- and multimolecular RNA G-quadruplex structures. Journal of Biological Chemistry 288(14), 9860-9866. Abstract  |  Full Text

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