Hereditary sensory and autonomic neuropathy type II (HSAN2) is characterized by progressively reduced sensation to pain, temperature, and touch. Onset can be at birth and is often before puberty. The sensory deficit is predominantly distal with the lower limbs more severely affected than the upper limbs. Over time sensory function becomes severely reduced. Unnoticed injuries and neuropathic skin promote ulcerations and infections that result in spontaneous amputation of digits or the need for surgical amputation. Osteomyelitis is common. Painless fractures can complicate the disease. Autonomic disturbances are variable and can include hyperhidrosis, tonic pupils, and urinary incontinence in those with more advanced disease.

Autosomal recessive spinocerebellar ataxia-32 (SCAR32) is a neurologic disorder characterized by the onset of gait ataxia in the second or third decades of life. The disorder is slowly progressive. Other classic features include upper limb ataxia, oculomotor signs, dysphagia, and dysarthria. Some patients may have hyper- or hypokinetic movement abnormalities. Brain imaging shows cerebellar atrophy (Rebelo et al., 2021).