| HTRA1 mutations | Associated with PLS and neurodegeneration[@sepulvedafalla2014] |
| Absence of muscle atrophy | PLS patients maintain muscle bulk |
| No fasciculations | Lower motor neuron signs are absent |
| Slower progression | Disease course extends over decades |
| Preserved sensory examination | Sensory function remains intact |
| Databases | OMIMOrphanetClinicalTrialsPubMed |