Although we have shown early dysfunction in motor neurons in AR100 mice, such as ER stress (Montague et al., 2014) and transcriptional dysregulation (Malik et al., 2019), we found that plasma levels of phosphorylated neurofilament heavy chain (pNfH), a marker of neuronal damage found to be altered in motor neuron diseases such as ALS, was unchanged in SBMA patients and AR100 mice (Lombardi et al., 2019). Here, NEFH is linked to motor neuron disorder.