AFP and cerebellar ataxia: Ataxia with Oculomotor Apraxia Type 2 (AOA2) presents as a progressive neurodegenerative disorder with adolescent-onset cerebellar ataxia, oculomotor apraxia in at least 50% of patients, elevated serum alpha-fetoprotein (AFP) levels, and peripheral sensorimotor axonal neuropathy leading to patients ultimately becoming unable to care for themselves (Anheim et al. 2009; Bennett and La Spada 2018; Fogel et al. 2014).