Phenotypes associated with the disease leukodystrophy, hypomyelinating, 9 (OMIM:616140):
- Poor head control (HP:0002421): Difficulty to maintain correct position of the head while standing or sitting. Infant head lag is observed when the head seems to flop around or lags posteriorly behind the trunk. Several articles have maintained that head lag should be absent by age 3 to 4 months. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Mild intellectual disability (HP:0001256): 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: 2/2. (PMID:24777941)
- Dysmetria (HP:0001310): A type of ataxia characterized by the inability to carry out movements with the correct range and motion across the plane of more than one joint related to incorrect estimation of the distances required for targeted movements. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Dystonia (HP:0001332): An abnormally increased muscular tone that causes fixed abnormal postures. There is a slow, intermittent twisting motion that leads to exaggerated turning and posture of the extremities and trunk. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Ataxia (HP:0001251): 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: PCS. Frequency: 2/4. (PMID:24777941)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 4/4. (PMID:24777941)
- Lower limb spasticity (HP:0002061): 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: 3/4. (PMID:24777941)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Intention tremor (HP:0002080): 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: PCS. Frequency: 1/4. (PMID:24777941)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 4/4. (PMID:24777941)
- Pseudobulbar paralysis (HP:0007024): Bilateral impairment of the function of the cranial nerves 9-12, which control musculature involved in eating, swallowing, and speech. Pseudobulbar paralysis is characterized clinically by dysarthria, dysphonia, and dysphagia with bifacial paralysis, and may be accompanied by Pseudobulbar behavioral symptoms such as enforced crying and laughing. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Leukodystrophy (HP:0002415): Leukodystrophy refers to deterioration of white matter of the brain resulting from degeneration of myelin sheaths in the CNS. Their basic defect is directly related to the synthesis and maintenance of myelin membranes. Symmetric white matter involvement at MRI is a typical finding in patients with leukodystrophies. Evidence: PCS. (PMID:24777941)
- Hyperreflexia (HP:0001347): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: PCS. (PMID:24777941)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Rotary nystagmus (HP:0001583): A form of nystagmus in which the eyeball makes rotary motions around the axis. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: PCS. Frequency: 2/4. (PMID:24777941)
- Babinski sign (HP:0003487): 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: 1/4. (PMID:24777941)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: PCS. (PMID:24777941)
- Feeding difficulties (HP:0011968): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Lower limb hyperreflexia (HP:0002395): Increased intensity of the a reflex in the leg. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Dysarthria (HP:0001260): 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: 1/4. (PMID:24777941)
- Global developmental delay (HP:0001263): A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age. Evidence: PCS. Frequency: 4/4. (PMID:24777941)
- Abnormality of extrapyramidal motor function (HP:0002071): A neurological condition related to lesions of the basal ganglia leading to typical abnormalities including akinesia (inability to initiate changes in activity and perform volitional movements rapidly and easily), muscular rigidity (continuous contraction of muscles with constant resistance to passive movement), chorea (widespread arrhythmic movements of a forcible, rapid, jerky, and restless nature), athetosis (inability to sustain the muscles of the fingers, toes, or other group of muscles in a fixed position), and akathisia (inability to remain motionless). Evidence: TAS. (OMIM:616140)
- Pendular nystagmus (HP:0012043): Rhythmic, involuntary sinusoidal oscillations of one or both eyes. The waveform of pendular nystagmus may occur in any direction. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Absent smooth pursuit (HP:0007179): A complete lack of the ability to track objects with the ocular smooth pursuit system, a class of rather slow eye movements that minimizes retinal target motion. Evidence: PCS. Frequency: 1/4. (PMID:24777941)
- Autosomal recessive inheritance (HP:0000007): 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:24777941)