While the relationship to ALS is still a bit murky, Lall and Baloh [101] have reviewed several models, one of which is based on the 50% under expression of C9orf72 observed in frontal cortex of ALS affected individuals, and the observations that C9orf72 deletion or knockdown in two animal models leads to motor neuron degeneration. Here, C9orf72 is linked to Motor neuron atrophy.