HDAC2 and amyotrophic lateral sclerosis: Janssen et al. (2010) found in ALS patients that HDAC2 expression was upregulated in motor cortex (in layers III–V, where upper motor neuron are located) and in spinal cord grey matter, particularly in the nuclei of motor neurons; they interpreted this result as a protective role of HDAC2 in ALS pathogenesis, although the mechanisms of this effect were not detailed.