- 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: Very frequent (HP:0040281). (ORPHA:580)
- Coarse facial features (HP:0000280): Absence of fine and sharp appearance of brows, nose, lips, mouth, and chin, usually because of rounded and heavy features or thickened skin with or without thickening of subcutaneous and bony tissues. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:580)
- Limitation of joint mobility (HP:0001376): A reduction in the freedom of movement of one or more joints. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:580)
- Abnormal heart morphology (HP:0001627): Any structural anomaly of the heart. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:580)
- 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: Very frequent (HP:0040281). (ORPHA:580)
- Inguinal hernia (HP:0000023): Protrusion of the contents of the abdominal cavity through the inguinal canal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Macroglossia (HP:0000158): Increased length and width of the tongue. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Gingival overgrowth (HP:0000212): Hyperplasia of the gingiva (that is, a thickening of the soft tissue overlying the alveolar ridge. The degree of thickening ranges from involvement of the interdental papillae alone to gingival overgrowth covering the entire tooth crown. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Full cheeks (HP:0000293): Increased prominence or roundness of soft tissues between zygomata and mandible. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Conductive hearing impairment (HP:0000405): An abnormality of vibrational conductance of sound to the inner ear leading to impairment of sensory perception of sound. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Sensorineural hearing impairment (HP:0000407): A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Retinopathy (HP:0000488): Any noninflammatory disease of the retina. This nonspecific term is retained here because of its wide use in the literature, but if possible new annotations should indicate the precise type of retinal abnormality. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Retinal degeneration (HP:0000546): A nonspecific term denoting progressive loss of the retinal pigment epithelium (RPE) and/or neurosensory retinal cells. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- 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:580)
- Decreased nerve conduction velocity (HP:0000762): A reduction in the speed at which electrical signals propagate along the axon of a neuron. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Dysostosis multiplex (HP:0000943). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Umbilical hernia (HP:0001537): Protrusion of abdominal contents through a defect in the abdominal wall musculature around the umbilicus. Skin and subcutaneous tissue overlie the defect. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Hoarse voice (HP:0001609): Hoarseness refers to a change in the pitch or quality of the voice, with the voice sounding weak, very breathy, scratchy, or husky. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Abnormal heart valve morphology (HP:0001654): Any structural abnormality of a cardiac valve. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Splenomegaly (HP:0001744): Abnormal increased size of the spleen. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Chronic diarrhea (HP:0002028): The presence of chronic diarrhea, which is usually taken to mean diarrhea that has persisted for over 4 weeks. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Heparan sulfate excretion in urine (HP:0002159): An increased concentration of heparan sulfates in the urine. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Progressive neurologic deterioration (HP:0002344). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Sleep disturbance (HP:0002360): An abnormal pattern in the quality, quantity, or characteristics of sleep. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Developmental regression (HP:0002376): Loss of developmental skills, as manifested by loss of developmental milestones. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Recurrent upper respiratory tract infections (HP:0002788): An increased susceptibility to upper respiratory tract infections as manifested by a history of recurrent upper respiratory tract infections (running ears - otitis, sinusitis, pharyngitis, tonsillitis). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Irregularity of vertebral bodies (HP:0004582). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Contractures of the large joints (HP:0005781). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- 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: Frequent (HP:0040282). (ORPHA:580)
- Peripheral visual field loss (HP:0007994): Loss of peripheral vision with retention of central vision, resulting in a constricted circular tunnel-like field of vision. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Dermatan sulfate excretion in urine (HP:0008301): An increased concentration of dermatan sulfate in the urine. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Sleep apnea (HP:0010535): An intermittent cessation of airflow at the mouth and nose during sleep is known as sleep apnea. Apneas that last at least 10 seconds are considered significant, but individuals with sleep apnea may experience apneas lasting from 20 seconds up to 2 or 3 minutes. Patients may have up to 15 events per hour of sleep. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Thick vermilion border (HP:0012471): Increased width of the skin of vermilion border region of upper lip. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Flexion contracture of digit (HP:0030044): A bent (flexed) finger or toe joint that cannot be straightened actively or passively. It is thus a chronic loss of joint motion due to structural changes in muscle, tendons, ligaments, or skin that prevents normal movement of joints. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Enlarged tonsils (HP:0030812): Increase in size of the tonsils, small collections of lymphoid tissue facing into the aerodigestive tract on either side of the back part of the throat. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Cognitive impairment (HP:0100543): Abnormal cognition is characterized by deficits in thinking, reasoning, or remembering. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- Recurrent ear infections (HP:0410018): Increased susceptibility to ear infections as manifested by recurrent episodes of ear infections. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:580)
- 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:580)
- Otosclerosis (HP:0000362): In otosclerosis, a callus of bone accumulates on the stapes creating a partial fixation. This limits the movement of the stapes bone, which results in hearing loss. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Wide nasal bridge (HP:0000431): Increased breadth of the nasal bridge (and with it, the nasal root). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Wide nose (HP:0000445): Interalar distance more than two standard deviations above the mean for age, i.e., an apparently increased width of the nasal base and alae. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Optic atrophy (HP:0000648): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Hyperactivity (HP:0000752): Hyperactivity is a condition characterized by constant and unusually high levels of activity, even in situations where it is deemed inappropriate. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Papilledema (HP:0001085): Papilledema refers to edema (swelling) of the optic disc secondary to any factor which increases cerebral spinal fluid pressure. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- 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: Occasional (HP:0040283). (ORPHA:580)
- Communicating hydrocephalus (HP:0001334): A form of hydrocephalus in which there is no visible obstruction to the flow of the cerebrospinal fluid between the ventricles and subarachnoid space. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Hip dysplasia (HP:0001385): The presence of developmental dysplasia of the hip. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal mitral valve morphology (HP:0001633): Any structural anomaly of the mitral valve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Cardiomyopathy (HP:0001638): A myocardial disorder in which the heart muscle is structurally and functionally abnormal, in the absence of coronary artery disease, hypertension, valvular disease and congenital heart disease sufficient to cause the observed myocardial abnormality. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal pulmonary valve morphology (HP:0001641): Any structural abnormality of the pulmonary valve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal aortic morphology (HP:0001679): An abnormality of the aorta. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal tricuspid valve morphology (HP:0001702): Any structural anomaly of the tricuspid valve. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Spinal cord compression (HP:0002176): External mechanical compression of the spinal cord. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Upper airway obstruction (HP:0002781): Increased resistance to the passage of air in the upper airway. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Muscle stiffness (HP:0003552): A condition in which muscles cannot be moved quickly without accompanying pain or spasm. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal retinal pigmentation (HP:0007703): Any deviation from the normal pigmentation of the retina. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Corneal opacity (HP:0007957): A reduction of corneal clarity. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Hip osteoarthritis (HP:0008843). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal epiphyseal ossification (HP:0010656): An abnormality of the formation and mineralization of an epiphysis. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Constrictive median neuropathy (HP:0012185): Injury to the median nerve caused by its entrapment at the wrist as it traverses through the carpal tunnel. Clinically, constrictive median neuropathy is characterized by pain, paresthesia, and weakness in the median nerve distribution of the hand. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Temporomandibular joint ankylosis (HP:0012478): Bony fusion of the mandibular condyle to the base of the skull, resulting in limitation of jaw opening. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal full-field electroretinogram (HP:0030466): An anomaly observed by full-field electroretinogram (ffERG). The ffERG measures the light-induced electrical activity of the retina at the corneal surface. Specifically, the ffERG records the global or total retinal electrical response to a full-field (Ganzfield) light stimulus. Isolation of the rod and cone components has important diagnostic value in differentiating between various retinal diseases. Modifying the properties of the light-stimulus (wavelength, strength, and flicker rate) as well as the adaptive state of the retina can separate the rod and cone functions of the ffERG. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- Abnormal nasal mucus secretion (HP:0031416): Any deviation from the normal quantity of secretion of nasal mucus, a thick viscous liquid produced by the mucous membranes of the nose. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:580)
- 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: Very rare (HP:0040284). (ORPHA:580)
- Hypertension (HP:0000822): The presence of chronic increased pressure in the systemic arterial system. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:580)
- Large central visual field defect (HP:0001129). Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:580)
- 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 rare (HP:0040284). (ORPHA:580)
- Arrhythmia (HP:0011675): Any cardiac rhythm other than the normal sinus rhythm. Such a rhythm may be either of sinus or ectopic origin and either regular or irregular. An arrhythmia may be due to a disturbance in impulse formation or conduction or both. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:580)
- Abnormal temper tantrums (HP:0025160): Temper tantrums are brief episodes of extreme, unpleasant, and sometimes aggressive behaviors in response to frustration or anger, which are a normal part of development in toddlers. Temper tantrums that occur more frequently in a given time and/or are more severe in symptomatology and/or longer in duration and/or inappropriate for the given age compared to a temper tantrum that naturally occurs as a part of the developmental process are classified as abnormal temper tantrums. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:580)
- Impulsivity (HP:0100710): Acting on the spur of the moment or on a momentary basis without consideration of outcomes; having difficulty establishing or following plans; experiencing a sense of urgency and engaging in behavior that is uninhibited, cannot be inhibited, and is uncontrolled. The possibility of repression is inconceivable. Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:580)
These phenotypes are associated with the disease Mucopolysaccharidosis type 2 (ORPHA:580).