We present a case of a 31 year old microcephalic male with childhood onset motor and gait difficulties. His symptoms began at age 5 with frequent falls, and by age 8 (3 years after symptom onset), he was wheel-chair bound. His motor weakness has continued to progress throughout adulthood, affecting both upper and lower extremities symmetrically with loss of deep tendon reflexes. His exam shows no evidence of upper motor neuron involvement. He has also developed chronic respiratory failure secondary to restrictive lung disease. There was concern for SMA, and a hereditary motor neuropathy genetic panel was ordered, which showed a heterozygous mutation in VRK1: one known pathogenic variant (c.266G>A) and one variant of uncertain significance (c.961C>T).

As more patients are diagnosed with motor pathologies associated with VRK1 mutations, the collective data will help elucidate the full spectrum of phenotypes and which variants are clinically significant.