This study estimated the number of prevalent and incident ALS cases overall and superoxide dismutase 1 (SOD1) and chromosome 9 open reading frame 72 (C9orf72) ALS from 22 countries. A literature review was conducted to identify population-based studies reporting ALS prevalence and/or incidence rates. The results suggest that although the proportions of SOD1 and C9orf72 are higher among those with familial ALS, the majority of SOD1 and C9orf72 ALS cases may be found among those with sporadic ALS. This suggests that classification of familial ALS based on reported family history does not capture the full picture of ALS of genetic origin. Click here to read the full paper.
