- 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: PCS. Frequency: 0/14. (PMID:29100089)
- Epicanthus (HP:0000286): A fold of skin starting above the medial aspect of the upper eyelid and arching downward to cover, pass in front of and lateral to the medial canthus. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Strabismus (HP:0000486): A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Generalized non-motor (absence) seizure (HP:0002121): A generalized non-motor (absence) seizure is a type of a type of dialeptic seizure that is of electrographically generalized onset. It is a generalized seizure characterized by an interruption of activities, a blank stare, and usually the person will be unresponsive when spoken to. Any ictal motor phenomena are minor in comparison to these non-motor features. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 7/14. (PMID:29100089)
- Short femur (HP:0003097): An abnormal shortening of the femur. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. (PMID:29100089)
- Ventricular septal defect (HP:0001629): A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 0/14. (PMID:29100089)
- Microtia (HP:0008551): Underdevelopment of the external ear. Evidence: PCS. Frequency: 0/14. (PMID:29100089)
- Overgrowth (HP:0001548): Excessive postnatal growth which may comprise increased weight, increased length, and/or increased head circumference. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Unsteady gait (HP:0002317). Evidence: PCS. Frequency: 0/14. (PMID:29100089)
- Genu valgum (HP:0002857): The legs angle inward, such that the knees are close together and the ankles far apart. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Gastrointestinal dysmotility (HP:0002579): Abnormal intestinal contractions, such as spasms and intestinal paralysis, related to the loss of the ability of the gut to coordinate muscular activity because of endogenous or exogenous causes. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 2/14. (PMID:29100089)
- Frontal upsweep of hair (HP:0002236): Upward and/or sideward growth of anterior hair. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 14/14. (PMID:29100089)
- Wide mouth (HP:0000154): Distance between the oral commissures more than 2 SD above the mean. Alternatively, an apparently increased width of the oral aperture (subjective). Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/14. Onset: Infantile onset (HP:0003593). (PMID:29100089)
- Downslanted palpebral fissures (HP:0000494): The palpebral fissure inclination is more than two standard deviations below the mean. Evidence: PCS. Frequency: 2/14. (PMID:29100089)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 1/14. (PMID:29100089)
- Absent speech (HP:0001344): Complete lack of development of speech and language abilities. Evidence: PCS. (PMID:29100089)
- 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: PCS. Frequency: 13/14. (PMID:29100089)
- EEG abnormality (HP:0002353): Abnormality observed by electroencephalogram (EEG), which is used to record of the brain's spontaneous electrical activity from multiple electrodes placed on the scalp. Evidence: PCS. Frequency: 2/14. (PMID:29100089)
- 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: PCS. Frequency: 1/14. (PMID:29100089)
- Delayed ability to walk (HP:0031936): A failure to achieve the ability to walk at an appropriate developmental stage. Most children learn to walk in a series of stages, and learn to walk short distances independently between 12 and 15 months. Evidence: PCS. (PMID:29100089)
- 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: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 2/14. (PMID:29100089)
- 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: 12/14. (PMID:29100089)
- Delayed gross motor development (HP:0002194): A type of motor delay characterized by a delay in acquiring the ability to control the large muscles of the body for walking, running, sitting, and crawling. Evidence: PCS. Frequency: 12/14. (PMID:29100089)
- Posterior plagiocephaly (HP:0011327): Asymmetry of the posterior part of the skull. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Thick corpus callosum (HP:0007074): Increased vertical dimension of the corpus callosum. This feature can be visualized by sagittal sections on magnetic resonance tomography imaging of the brain. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Blue nevus (HP:0100814): A solitary, bluish, smooth surfaced macule, papule or plaque that is generally round or oval in shape. The histopathology of blue nevi varies by subtype, but general characteristics include a vertical wedge or bulbous shaped proliferation of spindle cells, dendritic melanocytes, and melanophages into a sclerotic dermis or subcutis. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Hyperintensity of cerebral white matter on MRI (HP:0030890): A brighter than expected signal on magnetic resonance imaging emanating from the cerebral white matter. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Hypotelorism (HP:0000601): Interpupillary distance less than 2 SD below the mean (alternatively, the appearance of an decreased interpupillary distance or closely spaced eyes). Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Visual impairment (HP:0000505): Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery. Evidence: PCS. Frequency: 0/14. (PMID:29100089)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Autosomal dominant inheritance (HP:0000006): 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 heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele. Evidence: PCS. (PMID:29100089)
- 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: PCS. Frequency: 1/14. (PMID:29100089)
- 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: PCS. Frequency: 1/14. (PMID:29100089)
- Duodenal atresia (HP:0002247): A developmental defect resulting in complete obliteration of the duodenal lumen, that is, an abnormal closure of the duodenum. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Intestinal malrotation (HP:0002566): An abnormality of the intestinal rotation and fixation that normally occurs during the development of the gut. This can lead to volvulus, or twisting of the intestine that causes obstruction and necrosis. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
- Involuntary movements (HP:0004305): Involuntary contractions of muscle leading to involuntary movements of extremities, neck, trunk, or face. Evidence: PCS. Frequency: 2/14. (PMID:29100089)
- Hydronephrosis (HP:0000126): Severe distention of the kidney with dilation of the renal pelvis and calices. Evidence: PCS. Frequency: 1/14. (PMID:29100089)
These phenotypes are associated with the disease intellectual disability, autosomal dominant 53 (OMIM:617798).