This finding may be explained on the basis of potential sex-related factors, including environmental, lifestyle, or hormonal factors, that may moderate pathogenic mechanisms and influence an older age of onset and longer survival in women, allowing for reaching the age of complete penetrance and expression of the C9orf72-related ALS phenotype [23,104], considering that penetrance of C9orf72 expansions has been shown to increase with age [23,27]. The gene discussed is C9orf72; the disease is amyotrophic lateral sclerosis.