- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Irritability (HP:0000737): 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Delayed speech and language development (HP:0000750): A degree of language development that is significantly below the norm for a child of a specified age. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Lethargy (HP:0001254): A state of fatigue, either physical or mental slowness and sluggishness, with difficulties in initiating or performing simple tasks. Distinguished from apathy which implies indifference and a lack of desire or interest in the task. A person with lethargy may have the desire, but not the energy to engage in personal or socially relevant tasks. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Parkinsonism (HP:0001300): Characteristic neurologic anomaly resulting from degeneration of dopamine-generating cells in the substantia nigra, a region of the midbrain, characterized clinically by shaking, rigidity, slowness of movement and difficulty with walking and gait. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Brisk reflexes (HP:0001348): 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Pes cavus (HP:0001761): An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Talipes equinovarus (HP:0001762): Talipes equinovarus (also called clubfoot) typically has four main components: inversion and adduction of the forefoot; inversion of the heel and hindfoot; equinus (limitation of extension) of the ankle and subtalar joint; and internal rotation of the leg. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Constipation (HP:0002019): Infrequent or difficult evacuation of feces. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Rigidity (HP:0002063): Continuous involuntary sustained muscle contraction. When an affected muscle is passively stretched, the degree of resistance remains constant regardless of the rate at which the muscle is stretched. This feature helps to distinguish rigidity from muscle spasticity. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Gait ataxia (HP:0002066): 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: Frequent (HP:0040282). (ORPHA:101150)
- Bradykinesia (HP:0002067): Bradykinesia literally means slow movement, and is used clinically to denote a slowness in the execution of movement (in contrast to hypokinesia, which is used to refer to slowness in the initiation of movement). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- 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. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Postural tremor (HP:0002174): A type of tremors that is triggered by holding a limb in a fixed position. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Hypokinesia (HP:0002375): Abnormally diminished motor activity. In contrast to paralysis, hypokinesia is not characterized by a lack of motor strength, but rather by a poverty of movement. The typical habitual movements (e.g., folding the arms, crossing the legs) are reduced in frequency. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Lower limb hyperreflexia (HP:0002395): Increased intensity of the a reflex in the leg. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Limb dystonia (HP:0002451): A type of dystonia (abnormally increased muscular tone causing fixed abnormal postures) that affects muscles of the limbs. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Excessive salivation (HP:0003781): Excessive production of saliva. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Decreased CSF homovanillic acid concentration (HP:0003785): Decreased concentration of homovanillic acid (HVA) in the cerebrospinal fluid. HVA is a metabolite of dopamine. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Focal dystonia (HP:0004373): A type of dystonia that is localized to a specific part of the body. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Oculogyric crisis (HP:0010553): An acute dystonic reaction with blepharospasm, periorbital twitches, and protracted fixed staring episodes. There may be a maximal upward deviation of the eyes in the sustained fashion. Oculogyric crisis can be triggered by a number of factors including neuroleptic medications. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Feeding difficulties (HP:0011968): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- Night sweats (HP:0030166): Occurrence of excessive sweating during sleep. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:101150)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:101150)
- Fever (HP:0001945): Body temperature elevated above the normal range. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:101150)
- Generalized dystonia (HP:0007325): A type of dystonia that affects all or most of the body. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:101150)
- Generalized hypotonia (HP:0001290): Generalized muscular hypotonia (abnormally low muscle tone). Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:101150)
- Progressive encephalopathy (HP:0002448). Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:101150)
These phenotypes are associated with the disease Autosomal recessive dopa-responsive dystonia (ORPHA:101150).