Ismail and colleagues report on a high concurrence rate of multiple sclerosis (MS) and ALS.  Interestingly, the C9orf72 expansion was identified in 80% of the ALS-MS patients.  Given that the inflammatory system appears to be deregulated in patients expressing the c9orf72 expansion, with down-regulation of the neuroprotective CXCL10 chemokine and dysfunction of NF-kB activity,   the findings in the present study imply a role for inflammation in ALS.  The implications being that modulation of these neuroinflammatory pathways may prove therapeutically useful in ALS, especially given that c0orf72 expansions may be identified in up to20% of sporadic ALS patients.

Ismail et al.  Concurrence of multiple sclerosis and amyotrophic lateral sclerosis in patients with hexanucleotide repeat expansions of C9ORF72. J Neurol Neurosurg Psychiatry 2013;84:79-87 doi:10.1136/jnnp-2012-303326.