- 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: Very frequent (HP:0040281). (ORPHA:364028)
- 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:364028)
- 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: Frequent (HP:0040282). (ORPHA:364028)
- 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: Frequent (HP:0040282). (ORPHA:364028)
- Specific learning disability (HP:0001328): Impairment of certain skills such as reading or writing, coordination, self-control, or attention that interfere with the ability to learn. The impairment is not related to a global deficiency of intelligence. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:364028)
- Slender build (HP:0001533): Asthenic habitus refers to a slender build with long limbs, an angular profile, and prominent muscles or bones. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:364028)
- Moderate intellectual disability (HP:0002342): Moderate intellectual disability (ID) is defined as a type of ID characterized by moderately sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 35-49. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:364028)
- Cryptorchidism (HP:0000028): Testis in inguinal canal. That is, absence of one or both testes from the scrotum owing to failure of the testis or testes to descend through the inguinal canal to the scrotum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Micropenis (HP:0000054): Abnormally small penis. At birth, the normal penis is about 3 cm (stretched length from pubic tubercle to tip of penis) with micropenis less than 2.0-2.5 cm. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Hydronephrosis (HP:0000126): Severe distention of the kidney with dilation of the renal pelvis and calices. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Short upper lip (HP:0000188): Decreased width of the upper lip. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Narrow palate (HP:0000189): Width of the palate more than 2 SD below the mean (objective) or apparently decreased palatal width (subjective). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Open mouth (HP:0000194): A facial appearance characterized by a permanently or nearly permanently opened mouth. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Brachycephaly (HP:0000248): An abnormality of skull shape characterized by a decreased anterior-posterior diameter. That is, a cephalic index greater than 81%. Alternatively, an apparently shortened anteroposterior dimension (length) of the head compared to width. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Macrocephaly (HP:0000256): Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Malar flattening (HP:0000272): Underdevelopment of the malar prominence of the jugal bone (zygomatic bone in mammals), appreciated in profile, frontal view, and/or by palpation. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Facial hypotonia (HP:0000297): Reduced muscle tone of a muscle that is innervated by the facial nerve (the seventh cranial nerve). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Mandibular prognathia (HP:0000303): Abnormal prominence of the chin related to increased length of the mandible. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Short philtrum (HP:0000322): Distance between nasal base and midline upper lip vermilion border more than 2 SD below the mean. Alternatively, an apparently decreased distance between nasal base and midline upper lip vermilion border. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Prominent supraorbital ridges (HP:0000336): Greater than average forward and/or lateral protrusion of the supraorbital portion of the frontal bones. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Macrotia (HP:0000400): Median longitudinal ear length greater than two standard deviations above the mean and median ear width greater than two standard deviations above the mean (objective); or, apparent increase in length and width of the pinna (subjective). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Deeply set eye (HP:0000490): An eye that is more deeply recessed into the plane of the face than is typical. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- 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: Occasional (HP:0040283). (ORPHA:364028)
- Macrodontia of permanent maxillary central incisor (HP:0000675): Increased size of the maxillary central secondary incisor tooth. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- 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:364028)
- 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:364028)
- Self-mutilation (HP:0000742): Deliberate harm to one's body resulting in tissue damage, without a conscious intent to die. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Reduced eye contact (HP:0000817): A reduced frequency or duration of eye contact. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- 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:364028)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Cerebellar vermis hypoplasia (HP:0001320): Underdevelopment of the vermis of cerebellum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Myoclonus (HP:0001336): Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Pes planus (HP:0001763): A foot where the longitudinal arch of the foot is in contact with the ground or floor when the individual is standing; or, in a patient lying supine, a foot where the arch is in contact with the surface of a flat board pressed against the sole of the foot by the examiner with a pressure similar to that expected from weight bearing; or, the height of the arch is reduced. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Bilateral tonic-clonic seizure (HP:0002069): A bilateral tonic-clonic seizure is a seizure defined by a tonic (bilateral increased tone, lasting seconds to minutes) and then a clonic (bilateral sustained rhythmic jerking) phase. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- 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:364028)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Distal muscle weakness (HP:0002460): Reduced strength of the musculature of the distal extremities. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Recurrent infections (HP:0002719): Increased susceptibility to infections as manifested by repeated bouts of infection. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Kyphosis (HP:0002808): Exaggerated anterior convexity of the thoracic vertebral column. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Genu recurvatum (HP:0002816): An abnormally increased extension of the knee joint, so that the knee can bend backwards. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- 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: Occasional (HP:0040283). (ORPHA:364028)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Severe expressive language delay (HP:0006863): A severe delay in the acquisition of the ability to use language to communicate needs, wishes, or thoughts. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Retrocerebellar cyst (HP:0006951). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Sleep-wake cycle disturbance (HP:0006979): Any abnormality of an individual's circadian rhythm that affects the timing of sleeping and being awake is referred to as a sleep-wake disorder. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Pain insensitivity (HP:0007021): Inability to perceive painful stimuli. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Eversion of lateral third of lower eyelids (HP:0007655). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Uplifted earlobe (HP:0009909): An abnormal orientation of the earlobes such that they point out- and upward. That is, the lateral surface of ear lobe faces superiorly. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Severe intellectual disability (HP:0010864): Severe intellectual disability (ID) is defined as a type of ID characterized by severely sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) the range of 20-34. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Thick vermilion border (HP:0012471): Increased width of the skin of vermilion border region of upper lip. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
- Abnormality of muscle size (HP:0030236): Abnormalities of the overall muscle bulk based on clinical observation. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:364028)
These phenotypes are associated with the disease X-linked intellectual disability due to GRIA3 mutations (ORPHA:364028).