Phenotypes associated with the disease hypomyelination with brain stem and spinal cord involvement and leg spasticity (OMIM:615281, an entry in Online Mendelian Inheritance in Man):
- Axial hypotonia (HP:0008936, a Human Phenotype Ontology term): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 8/10. (PMID:23643384)
- Progressive (HP:0003676, a Human Phenotype Ontology term): Applies to a disease manifestation that increases in scope or severity over the course of time, i.e., that worsens with age. Evidence: PCS. (PMID:23643384)
- Spastic diplegia (HP:0001264, a Human Phenotype Ontology term): Spasticity (neuromuscular hypertonia) primarily in the muscles of the legs, hips, and pelvis. Evidence: PCS. Frequency: 3/10. (PMID:23643384)
- Mild intellectual disability (HP:0001256, a Human Phenotype Ontology term): Mild intellectual disability (ID) is defined as a type of ID characterized by mildly sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 50-69. Evidence: PCS. Frequency: 4/10. (PMID:23643384)
- Tethered cord (HP:0002144, a Human Phenotype Ontology term): During normal embryological development, the spinal cord first occupies the entire length of the vertebral column but goes on to assume a position at the level of L1 due to differential growth of the conus medullaris and the vertebral column. The filum terminale is a slender, threadlike structure that remains after the normal regression of the distal embryonic spinal cord and attaches the spinal cord to the coccyx. A tethered cord results if there is a thickened rope-like filum terminale which anchors the cord at the level of L2 or below, potentially causing neurologic signs owing to abnormal tension on the spinal cord. Evidence: PCS. Frequency: 1/10. (PMID:23643384)
- 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: PCS. Frequency: 10/10. (PMID:23643384)
- Hypoplasia of the corpus callosum (HP:0002079, a Human Phenotype Ontology term): Underdevelopment of the corpus callosum. Evidence: PCS. Frequency: 8/10. (PMID:23643384)
- Seizure (HP:0001250, a Human Phenotype Ontology term): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: PCS. Frequency: 2/10. (PMID:23643384)
- Leukoencephalopathy (HP:0002352, a Human Phenotype Ontology term): This term describes abnormality of the white matter of the cerebrum resulting from damage to the myelin sheaths of nerve cells. Evidence: PCS. (PMID:23643384)
- Spina bifida occulta (HP:0003298, a Human Phenotype Ontology term): The closed form of spina bifida with incomplete closure of a vertebral body with intact overlying skin. Evidence: PCS. Frequency: 1/10. (PMID:23643384)
- Dysarthria (HP:0001260, a Human Phenotype Ontology term): Dysarthric speech is a general description referring to a neurological speech disorder characterized by poor articulation. Depending on the involved neurological structures, dysarthria may be further classified as spastic, flaccid, ataxic, hyperkinetic and hypokinetic, or mixed. Evidence: PCS. Frequency: 3/10. (PMID:23643384)
- Infantile onset (HP:0003593, a Human Phenotype Ontology term): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 9/10. (PMID:23643384)
- Cherry red spot of the macula (HP:0010729, a Human Phenotype Ontology term): Pallor of the perifoveal macula of the retina with appearance of a small circular reddish choroid shape as seen through the fovea centralis due to relative transparency of the macula. Evidence: PCS. Frequency: 1/10. (PMID:23643384)
- Ataxia (HP:0001251, a Human Phenotype Ontology term): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: IEA. Frequency: 4/9. (PMID:23643384)
- Lower limb spasticity (HP:0002061, a Human Phenotype Ontology term): Spasticity (velocity-dependent increase in tonic stretch reflexes with increased muscle tone and hyperexcitable tendon reflexes) in the muscles of the lower limbs, hips, and pelvis. Evidence: PCS. Frequency: 10/10. (PMID:23643384)
- Motor delay (HP:0001270, a Human Phenotype Ontology term): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: PCS. Frequency: 3/10. (PMID:23643384)
- 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: PCS. Frequency: 5/10. (PMID:23643384)
- Childhood onset (HP:0011463, a Human Phenotype Ontology term): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/10. (PMID:23643384)
- Irritability (HP:0000737, a Human Phenotype Ontology term): An emotional state characterized by negative feelings of heightened frustration, annoyance, or feeling upset, often triggered by internal factors (e.g., fatigue, hunger, unfulfilled desires) or external factors (e.g., social or environmental challenges). Irritability may be unpredictable, and is accompanied by a lowered threshold for emotional reactivity and observable features (speech, facial expressions, or psychomotor activity). Evidence: PCS. Frequency: 2/10. (PMID:23643384)
- Autosomal recessive inheritance (HP:0000007, a Human Phenotype Ontology term): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:23643384)
- CNS hypomyelination (HP:0003429, a Human Phenotype Ontology term): Reduced amount of myelin in the central nervous system resulting from defective myelinogenesis. Evidence: PCS. Frequency: 5/9. (PMID:23643384)
- 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: PCS. Frequency: 3/10. (PMID:23643384)
- Brisk reflexes (HP:0001348, a Human Phenotype Ontology term): Tendon reflexes that are noticeably more active than usual (conventionally denoted 3+ on clinical examination). Brisk reflexes may or may not indicate a neurological lesion. They are distinguished from hyperreflexia by the fact that hyerreflexia is characterized by hyperactive repeating (clonic) reflexes, which are considered to be always abnormal. Evidence: PCS. Frequency: 10/10. (PMID:23643384)