PARK7 and amyotrophic lateral sclerosis: Although no direct evidence of copper-induced mitochondrial dysfunction has been reported in the development of ALS, changes in certain copper-dependent enzymes such as PARK7, COX1, and COX2 have been shown to trigger neuronal death through regulation of mitochondrial function (Fujita et al., 1996; Borthwick et al., 1999; Wang et al., 2016).