- Atypical behavior (HP:0000708): Atypical behavior is an abnormality in a person's actions that can be controlled or modulated by the will of the individual. While abnormal behaviors can be difficult to control, they are distinct from other abnormal actions that cannot be affected by the individual's will. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Intellectual disability (HP:0001249): 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: Very frequent (HP:0040281). (ORPHA:79101)
- Seizure (HP:0001250): 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Abnormal cerebrospinal fluid morphology (HP:0002921): An abnormality of the cerebrospinal fluid (CSF). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Hydroxyprolinuria (HP:0003080): An increased concentration of 4-hydroxy-L-proline in the urine. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Prolinuria (HP:0003137): Level of proline in the urine anove the upper limit of normal. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Hyperprolinemia (HP:0008358): The concentration of proline in the blood circulation is above the upper limit of normal. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Abnormal circulating enzyme concentration or activity (HP:0012379): Concentration or activity of an enzyme is above or below the limits of normal in the blood circulation. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- Increased urine alpha-ketoglutarate concentration (HP:0012402): A greater than normal concentration of 2-oxoglutaric acid in the urine. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:79101)
- 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:79101)
- Hyperglycinemia (HP:0002154): An elevated concentration of glycine in the blood. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Generalized-onset seizure (HP:0002197): A generalized-onset seizure is a type of seizure originating at some point within, and rapidly engaging, bilaterally distributed networks. The networks may include cortical and subcortical structures but not necessarily the entire cortex. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Unsteady gait (HP:0002317). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Increased CSF protein concentration (HP:0002922): Increased concentration of protein in the cerebrospinal fluid. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Hyperalaninemia (HP:0003348): An increased concentration of alanine in the blood. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Muscle spasm (HP:0003394): Sudden and involuntary contractions of one or more muscles. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Exercise intolerance (HP:0003546): A functional motor deficit where individuals whose responses to the challenges of exercise fail to achieve levels considered normal for their age and gender. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Reduced circulating vitamin B6 circulating (HP:0008326): An abnormally decreased concentration of vitamin B6 in the blood circulation. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- EEG with generalized sharp slow waves (HP:0011199): EEG with generalized sharp transient waves of a duration between 80 and 200 msec followed by a slow wave. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Chronic fatigue (HP:0012432): Subjective feeling of tiredness characterized by a lack of energy and motivation that persists for six months or longer. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:79101)
- Renal insufficiency (HP:0000083): A reduction in the level of performance of the kidneys in areas of function comprising the concentration of urine, removal of wastes, the maintenance of electrolyte balance, homeostasis of blood pressure, and calcium metabolism. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Abnormality of eye movement (HP:0000496): An abnormality in voluntary or involuntary eye movements or their control. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Vertical supranuclear gaze palsy (HP:0000511): A supranuclear gaze palsy is an inability to look in a vertical direction as a result of cerebral impairment. There is a loss of the voluntary aspect of eye movements, but, as the brainstem is still intact, all the reflex conjugate eye movements are normal. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Ophthalmoparesis (HP:0000597): Ophthalmoplegia is a paralysis or weakness of one or more of the muscles that control eye movement. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Depression (HP:0000716): Frequently experiencing feelings of being down, miserable, and/or hopeless; struggling to recover from these moods; having a pessimistic outlook on the future; feeling a pervasive sense of shame; having a low self-worth; experiencing thoughts of suicide and engaging in suicidal behavior. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Aggressive behavior (HP:0000718): Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Autistic behavior (HP:0000729): Persistent deficits in social interaction and communication and interaction as well as a markedly restricted repertoire of activity and interest as well as repetitive patterns of behavior. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Short attention span (HP:0000736): Reduced attention span characterized by distractibility and impulsivity. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Hallucinations (HP:0000738): Perceptions in a conscious and awake state that, in the absence of external stimuli, have qualities of real perception. These perceptions are vivid, substantial, and located in external objective space. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Anxiety (HP:0000739): Intense feelings of nervousness, tension, or panic often arise in response to interpersonal stresses. There is worry about the negative effects of past unpleasant experiences and future negative possibilities. Individuals may feel fearful, apprehensive, or threatened by uncertainty, and they may also have fears of falling apart or losing control. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Areflexia (HP:0001284): Absence of neurologic reflexes such as the knee-jerk reaction. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Confusion (HP:0001289): Lack of clarity and coherence of thought, perception, understanding, or action. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Encephalopathy (HP:0001298): Encephalopathy is a term that means brain disease, damage, or malfunction. In general, encephalopathy is manifested by an altered mental state. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Psychotic mentation (HP:0001345): A pattern of thinking and perceiving characterized by a loss of contact with reality, leading to significant changes in thoughts, perceptions, and behaviors. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Diarrhea (HP:0002014): Abnormally increased frequency (usually defined as three or more) loose or watery bowel movements a day. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Dysphagia (HP:0002015): Difficulty in swallowing. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Abdominal pain (HP:0002027): An unpleasant sensation characterized by physical discomfort (such as pricking, throbbing, or aching) and perceived to originate in the abdomen. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Status epilepticus (HP:0002133): Status epilepticus is a type of prolonged seizure resulting either from the failure of the mechanisms responsible for seizure termination or from the initiation of mechanisms which lead to abnormally prolonged seizures (after time point t1). It is a condition that can have long-term consequences (after time point t2), including neuronal death, neuronal injury, and alteration of neuronal networks, depending on the type and duration of seizures. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Febrile seizure (within the age range of 3 months to 6 years) (HP:0002373): A febrile seizure is any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in children between the ages of 3 months and 6 years. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Increased CSF lactate (HP:0002490): Increased concentration of lactate in the cerebrospinal fluid. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Distal sensory impairment (HP:0002936): An abnormal reduction in sensation in the distal portions of the extremities. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Myalgia (HP:0003326): Pain in muscle. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Speech articulation difficulties (HP:0009088): Impairment in the physical production of speech sounds. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Peripheral neuropathy (HP:0009830): Peripheral neuropathy is a general term for any disorder of the peripheral nervous system. The main clinical features used to classify peripheral neuropathy are distribution, type (mainly demyelinating versus mainly axonal), duration, and course. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Atonic seizure (HP:0010819): Atonic seizure is a type of motor seizure characterized by a sudden loss or diminution of muscle tone without apparent preceding myoclonic or tonic event lasting about 1 to 2 seconds, involving head, trunk, jaw, or limb musculature. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Early onset absence seizures (HP:0011152): Typical absence seizures starting before the age of 4 years. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- Mild global developmental delay (HP:0011342): A mild delay in the achievement of motor or mental milestones in the domains of development of a child. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
- 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: Occasional (HP:0040283). (ORPHA:79101)
- Dysesthesia (HP:0012534): Painful sensations elicited by a nonpainful cutaneous stimulus such as a light touch or gentle stroking over affected areas of the body. Sometimes referred to as hyperpathia or hyperalgesia. Often perceived as an intense burning, dyesthesias may outlast the stimulus by several seconds. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:79101)
These phenotypes are associated with the disease Hyperprolinemia type 2 (ORPHA:79101).