A higher degree of neuronal cell death is observed in NER neurodegenerative diseases—the cerebellum of patients with CS, displays the loss of Purkinje cells, and mice with reduced expression of ERCC1, a protein involved in NER, show age-dependent motor neuron degeneration and astrogliosis, similar to amyotrophic lateral sclerosis (ALS) (Goetz, 2000; Kajitani et al., 2021). The gene discussed is ERCC1; the disease is Cowden syndrome 1.