- Progressive visual loss (HP:0000529, a Human Phenotype Ontology term): A reduction of previously attained ability to see. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Optic disc pallor (HP:0000543, a Human Phenotype Ontology term): A pale yellow discoloration of the optic disc (the area of the optic nerve head in the retina). The optic disc normally has a pinkish hue with a central yellowish depression. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Color vision defect (HP:0000551, a Human Phenotype Ontology term): An anomaly in the ability to discriminate between or recognize colors. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Central scotoma (HP:0000603, a Human Phenotype Ontology term): An area of depressed vision located at the point of fixation and that interferes with central vision. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Optic atrophy (HP:0000648, a Human Phenotype Ontology term): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Reduced visual acuity (HP:0007663, a Human Phenotype Ontology term). Evidence: TAS. Frequency: Frequent (HP:0040282, a Human Phenotype Ontology term). (ORPHA:98890)
- Nystagmus (HP:0000639, a Human Phenotype Ontology term): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Emotional lability (HP:0000712, a Human Phenotype Ontology term): Unstable emotional experiences and frequent mood changes; emotions that are easily aroused, intense, and/or disproportionate to events and circumstances. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Decreased nerve conduction velocity (HP:0000762, a Human Phenotype Ontology term): A reduction in the speed at which electrical signals propagate along the axon of a neuron. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Intellectual disability (HP:0001249, a Human Phenotype Ontology term): The term intellectual disability or intellectual developmental disorder is used to describe significantly sub-average intellectual and adaptive functioning based on clinical assessment and as measured by individually administered, appropriately normed, standardized and validated tests of intellectual functioning and adaptive behavior, with onset during the developmental period from infancy through adolescence. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Choreoathetosis (HP:0001266, a Human Phenotype Ontology term): Involuntary movements characterized by both athetosis (inability to sustain muscles in a fixed position) and chorea (widespread jerky arrhythmic movements). Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Gait ataxia (HP:0002066, a Human Phenotype Ontology term): A type of ataxia characterized by the impairment of the ability to coordinate the movements required for normal walking. Gait ataxia is characteirzed by a wide-based staggering gait with a tendency to fall. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Dysdiadochokinesis (HP:0002075, a Human Phenotype Ontology term): A type of ataxia characterized by the impairment of the ability to perform rapidly alternating movements, such as pronating and supinating his or her hand on the dorsum of the other hand as rapidly as possible. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Intention tremor (HP:0002080, a Human Phenotype Ontology term): A type of kinetic tremor that occurs during target directed movement is called intention tremor. That is, an oscillatory cerebellar ataxia that tends to be absent when the limbs are inactive and during the first part of voluntary movement but worsening as the movement continues and greater precision is required (e.g., in touching a target such as the patient's nose or a physician's finger). Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Babinski sign (HP:0003487, a Human Phenotype Ontology term): Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Asterixis (HP:0012164, a Human Phenotype Ontology term): A clinical sign indicating a lapse of posture and is usually manifest by a bilateral flapping tremor at the wrist, metacarpophalangeal, and hip joints. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
- Abnormal nervous system physiology (HP:0012638, a Human Phenotype Ontology term): A functional anomaly of the nervous system. Evidence: TAS. Frequency: Occasional (HP:0040283, a Human Phenotype Ontology term). (ORPHA:98890)
These phenotypes are associated with the disease Early-onset X-linked optic atrophy (ORPHA:98890, an Orphanet rare-disease identifier).