- Progressive (HP:0003676): 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:24562058)
- Spastic dysarthria (HP:0002464): A type of dysarthria related to bilateral damage of the upper motor neuron tracts of the pyramidal and extra- pyramidal tracts. Speech of affected individuals is slow, effortful, and has a harsh vocal quality. Evidence: TAS. (OMIM:205100)
- Short stature (HP:0004322): A height below that which is expected according to age and gender norms. Although there is no universally accepted definition of short stature, many refer to "short stature" as height more than 2 standard deviations below the mean for age and gender (or below the 3rd percentile for age and gender dependent norms). Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- 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: 1/3. (PMID:24562058)
- Delayed somatosensory central conduction time (HP:0100291): An abnormal increase (delay) in the somatosensory central conduction time (CCT), which can be measured from the peak of N13 to the peak of N20 (peak CCT) or from the onset of N11 to the onset of N20 (onset CCT). Evidence: PCS. Frequency: 0/1. (PMID:24562058)
- Spastic gait (HP:0002064): Spasticity is manifested by increased stretch reflex which is intensified with movement velocity. This results in excessive and inappropriate muscle activation which can contribute to muscle hypertonia. Spastic gait is characterized by manifestations such as muscle hypertonia, stiff knee, and circumduction of the leg. Evidence: TAS. (OMIM:205100)
- Distal muscle weakness (HP:0002460): Reduced strength of the musculature of the distal extremities. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- 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: 1/3. (PMID:24562058)
- 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: TAS. (OMIM:205100)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 3/3. (PMID:24562058)
- Proximal muscle weakness (HP:0003701): A lack of strength of the proximal muscles. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Muscle weakness (HP:0001324): Reduced strength of muscles. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Generalized dystonia (HP:0007325): A type of dystonia that affects all or most of the body. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Skeletal muscle atrophy (HP:0003202): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- EMG: chronic denervation signs (HP:0003444): Evidence of chronic denervation on electromyography. Evidence: TAS. (OMIM:205100)
- Spastic diplegia (HP:0001264): Spasticity (neuromuscular hypertonia) primarily in the muscles of the legs, hips, and pelvis. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 2/3. (PMID:24562058)
- 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: 1/3. (PMID:24562058)
- Limb joint contracture (HP:0003121): A contracture (chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin) that prevent normal movement of one or more joints of the limbs. Evidence: PCS. Frequency: 2/3. (PMID:24562058)
- 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: TAS. (OMIM:205100)
- 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: 1/3. (PMID:24562058)
- Pseudobulbar affect (HP:0002193): Pseudobulbar affect (PBA) is characterized by uncontrolled crying or laughing which may be disproportionate or inappropriate to the social context. Thus, there is a disparity between the patient's emotional expression and his or her emotional experience. Evidence: TAS. (OMIM:205100)
- Hand muscle atrophy (HP:0009130): Muscular atrophy involving the muscles of the hand. Evidence: IEA. (OMIM:205100)
- Amyotrophic lateral sclerosis (HP:0007354). Evidence: PCS. (PMID:24562058)
- 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:24562058)
- Drooling (HP:0002307): Habitual flow of saliva out of the mouth. Evidence: TAS. (OMIM:205100)
- Anarthria (HP:0002425): A defect in the motor ability that enables speech. Evidence: PCS. Frequency: 2/3. (PMID:24562058)
- Spasticity (HP:0001257): A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes. Evidence: PCS. Frequency: 3/3. (PMID:24562058)
- Upper limb spasticity (HP:0006986). Evidence: TAS. (OMIM:205100)
- Retrocollis (HP:0002544): A form of torticollis in which the head is drawn back, either due to a permanent contractures of neck extensor muscles, or to a spasmodic contracture. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Spasticity of pharyngeal muscles (HP:0002501). Evidence: TAS. (OMIM:205100)
- Hypertonia (HP:0001276): A condition in which there is increased muscle tone so that arms or legs, for example, are stiff and difficult to move. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Abnormal lower motor neuron morphology (HP:0002366): Any structural anomaly of the lower motor neuron. Evidence: IEA. (OMIM:205100)
- Clonus (HP:0002169): A series of rhythmic and involuntary muscle contractions (at a frequency of about 5 to 7 Hz) that occur in response to an abruptly applied and sustained stretch. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Abnormal speech pattern (HP:0002167): An abnormality in the sound (volume) or cadence (rate) of speech. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Distal amyotrophy (HP:0003693): Muscular atrophy affecting muscles in the distal portions of the extremities. Evidence: TAS. (OMIM:205100)
- Tongue muscle weakness (HP:0000183): Reduced strength of the tongue musculature, resulting in difficulties moving the tongue and possible accompanied by dysarthria or dysphagia. Evidence: TAS. (OMIM:205100)
- Urinary incontinence (HP:0000020): Loss of the ability to control the urinary bladder leading to involuntary urination. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Arm dystonia (HP:0031960): A type of dystonia (abnormally increased muscular tone causing fixed abnormal postures) that affects muscles of the arms. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Abnormal exteroceptive sensation (HP:0033747): A type of somatic sensory dysfunction characterized by abnormality of superficial sensation that is mediated by receptors in skin and mucous membranes. Evidence: PCS. Frequency: 0/3. (PMID:24562058)
- Head titubation (HP:0002599): A head tremor of moderate speed (3 to 4 Hz) in the anterior-posterior direction. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Hyperreflexia (HP:0001347): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Opisthotonus (HP:0002179): Opisthotonus is defined as a dramatic abnormal posture due to spastic contraction of the extensor muscles of the neck, trunk, and lower extremities that produces a severe backward arching from neck to heel. In most cases, the trunk is elevated off the ground by a few inches. It is usually sudden in onset and can be sustained or repetitive. It can be considered a variant of decerebrate posturing involving a hyperextension of the neck, back, and limbs. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Dysphagia (HP:0002015): Difficulty in swallowing. Evidence: IEA. (OMIM:205100)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: PCS. Frequency: 2/3. (PMID:24562058)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Spastic tetraparesis (HP:0001285): Spastic weakness affecting all four limbs. Evidence: TAS. (OMIM:205100)
- Spasticity of facial muscles (HP:0002491): Spasticity of one or more muscles innervated by the facial nerve. Evidence: TAS. (OMIM:205100)
- Tip-toe gait (HP:0030051): An abnormal gait pattern characterized by the failure of the heel to contact the floor at the onset of stance during gait. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Distal lower limb amyotrophy (HP:0008944): Muscular atrophy of distal leg muscles. Evidence: PCS. Frequency: 1/3. (PMID:24562058)
- Abnormal upper motor neuron morphology (HP:0002127): Any structural anomaly that affects the upper motor neuron. Evidence: IEA. (OMIM:205100)
These phenotypes are associated with the disease amyotrophic lateral sclerosis type 2, juvenile (OMIM:205100).