OCA2 and motor neuron disorder: Mutations within TFG have been associated with several distinct phenotypes, including HMSN‐P, (Alavi et al., 2015; Ishiura et al., 2012) hereditary spastic paraplegia (HSP), (Tariq & Naz, 2017) neuroaxonal dystrophy “plus” syndrome, (Catania, Battini, & Pippucci, 2018) and motor neuron disease with sensory neuropathy (Li, Meng, & Wu, 2019).