New research reveals that the most common mutation found in patients with amyotrophic lateral sclerosis (ALS) also causes autoimmunity in mice (Burberry A et al. Sci Transl Med. 2016;8:347ra93). The mutation, a hexanucleotide repeat expansion in the gene C9ORF72, is present in 4% to 8% of patients with sporadic ALS and 40% of familial ALS cases from Europe and the United States.
Collaborators led by investigators at the Harvard Stem Cell Institute, the Broad Institute of Massachusetts Institute of Technology, and Harvard discovered that mice harboring loss-of-function mutations in C9orf72 (the murine ortholog of C9ORF72) develop several classical features of autoimmunity such as splenomegaly and reduced hematocrit. In addition, when bone marrow cells with the mutation were transplanted into wild-type mice, the recipient mice developed autoimmunity and died prematurely. In contrast, transplantation of normal bone marrow lessened autoimmunity and prolonged life in C9orf72-deficient mice.
Hampton T. Study Provides Insights on ALS. JAMA. 2016;316(9):917. doi:10.1001/jama.2016.11071