Phenotypes associated with the disease Down syndrome (ORPHA:870):
- 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: Very frequent (HP:0040281). (ORPHA:870)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Short neck (HP:0000470): Diminished length of the neck. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Thickened nuchal skin fold (HP:0000474): A thickening of the skin thickness in the posterior aspect of the fetal neck. A nuchal fold (NF) measurement is obtained in a transverse section of the fetal head at the level of the cavum septum pellucidum and thalami, angled posteriorly to include the cerebellum. The measurement is taken from the outer edge of the occiput bone to the outer skin limit directly in the midline. An NF measurement greater than 5 mm at 14 to 17+6 weeks of gestation, or 6 mm at 18 to 28 weeks has been associated with a markedly increased risk for Down syndrome. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Upslanted palpebral fissure (HP:0000582): The palpebral fissure inclination is more than two standard deviations above the mean for age (objective); or, the inclination of the palpebral fissure is greater than typical for age. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Brachydactyly (HP:0001156): Digits that appear disproportionately short compared to the hand/foot. The word brachydactyly is used here to describe a series distinct patterns of shortened digits (brachydactyly types A-E). This is the sense used here. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- 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:870)
- 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: Very frequent (HP:0040281). (ORPHA:870)
- 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: Very frequent (HP:0040281). (ORPHA:870)
- 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: Very frequent (HP:0040281). (ORPHA:870)
- Depressed nasal bridge (HP:0005280): Posterior positioning of the nasal root in relation to the overall facial profile for age. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Increased total neutrophil count (HP:0011897): Abnormal increase of absolute number of neutrophils in the blood, per microliter, compared to a reference range for a given sex and age-group. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Flat face (HP:0012368): Absence of concavity or convexity of the face when viewed in profile. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Round ear (HP:0100830). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:870)
- Decreased fertility (HP:0000144). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Macroglossia (HP:0000158): Increased length and width of the tongue. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Narrow mouth (HP:0000160): Distance between the commissures of the mouth more than 2 SD below the mean. Alternatively, an apparently decreased width of the oral aperture (subjective). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormality of the dentition (HP:0000164): Any abnormality of the teeth. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Thick lower lip vermilion (HP:0000179): Increased thickness of the lower lip, leading to a prominent appearance of the lower lip. The height of the vermilion of the lower lip in the midline is more than 2 SD above the mean. Alternatively, an apparently increased height of the vermilion of the lower lip in the frontal view (subjective). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- 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: Frequent (HP:0040282). (ORPHA:870)
- Open mouth (HP:0000194): A facial appearance characterized by a permanently or nearly permanently opened mouth. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormal cranial suture/fontanelle morphology (HP:0000235): Any abnormality of the fontanelles (the regions covered by a thick membrane that normally ossify in the first two years of life) or the cranial sutures (the fibrous joints in which the articulating bones or cartilages of the skull are connected by sutural ligaments). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Depressed nasal ridge (HP:0000457): Lack of prominence of the nose resulting from a posteriorly-placed nasal ridge. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Broad neck (HP:0000475): Increased side-to-side width of the neck. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Microdontia (HP:0000691): Decreased size of the teeth, which can be defined as a mesiodistal tooth diameter (width) more than 2 SD below mean. Alternatively, an apparently decreased maximum width of tooth. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Obesity (HP:0001513): Accumulation of substantial excess body fat. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- 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:870)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Sandal gap (HP:0001852): A widely spaced gap between the first toe (the great toe) and the second toe. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormality of blood and blood-forming tissues (HP:0001871): An abnormality of the hematopoietic system. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Thrombocytopenia (HP:0001873): A reduction in the number of circulating thrombocytes. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Polycythemia (HP:0001901): Polycythemia is diagnosed if the red blood cell count, the hemoglobin level, and the red blood cell volume all exceed the upper limits of normal. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Duodenal atresia (HP:0002247): A developmental defect resulting in complete obliteration of the duodenal lumen, that is, an abnormal closure of the duodenum. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Developmental regression (HP:0002376): Loss of developmental skills, as manifested by loss of developmental milestones. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Alzheimer disease (HP:0002511): A degenerative disease of the brain characterized by the insidious onset of dementia. Impairment of memory, judgment, attention span, and problem solving skills are followed by severe apraxia and a global loss of cognitive abilities. The condition primarily occurs after age 60, and is marked pathologically by severe cortical atrophy and the triad of senile plaques, neurofibrillary tangles, and neuropil threads. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Downturned corners of mouth (HP:0002714): A morphological abnormality of the mouth in which the angle of the mouth is downturned. The oral commissures are positioned inferior to the midline labial fissure. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Short nose (HP:0003196): Distance from nasion to subnasale more than two standard deviations below the mean, or alternatively, an apparently decreased length from the nasal root to the nasal tip. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Clinodactyly of the 5th finger (HP:0004209): Clinodactyly refers to a bending or curvature of the fifth finger in the radial direction (i.e., towards the 4th finger). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- 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: Frequent (HP:0040282). (ORPHA:870)
- Atrioventricular canal defect (HP:0006695): A defect of the atrioventricular septum of the heart. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Prematurely aged appearance (HP:0007495). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Bilateral single transverse palmar creases (HP:0007598): The distal and proximal transverse palmar creases are merged into a single transverse palmar crease on both hands. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Protruding tongue (HP:0010808): Tongue extending beyond the alveolar ridges or teeth at rest. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormality of immune system physiology (HP:0010978): A functional abnormality of the immune system. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormal cardiovascular system morphology (HP:0030680): Any structural anomaly of the heart and blood vessels. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- Abnormality of the lymphatic system (HP:0100763): An anomaly of the lymphatic system, a network of lymphatic vessels that carry a clear fluid called lymph unidirectionally towards either the right lymphatic duct or the thoracic duct, which in turn drain into the right and left subclavian veins respectively. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:870)
- 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: Occasional (HP:0040283). (ORPHA:870)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Blepharitis (HP:0000498): Inflammation of the eyelids. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Cataract (HP:0000518): A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Myopia (HP:0000545): An abnormality of refraction characterized by the ability to see objects nearby clearly, while objects in the distance appear blurry. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Keratoconus (HP:0000563): A cone-shaped deformity of the cornea characterized by the presence of corneal distortion secondary to thinning of the apex. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Amblyopia (HP:0000646): Reduced visual acuity that is uncorrectable by lenses in the absence of detectable anatomic defects in the eye or visual pathways. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Delayed puberty (HP:0000823): Passing the age when puberty normally occurs with no physical or hormonal signs of the onset of puberty. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- 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: Occasional (HP:0040283). (ORPHA:870)
- Gait disturbance (HP:0001288): The term gait disturbance can refer to any disruption of the ability to walk. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Tetralogy of Fallot (HP:0001636): A congenital cardiac malformation comprising pulmonary stenosis, overriding aorta, ventricular septum defect, and right ventricular hypertrophy. The diagnosis of TOF is made if at least three of the four above mentioned features are present. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Secundum atrial septal defect (HP:0001684): A kind of atrial septum defect arising from an enlarged foramen ovale, inadequate growth of the septum secundum, or excessive absorption of the septum primum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Leukemia (HP:0001909): A cancer of the blood and bone marrow characterized by an abnormal proliferation of leukocytes. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Gastroesophageal reflux (HP:0002020): A condition in which the stomach contents leak backwards from the stomach into the esophagus through the lower esophageal sphincter. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Anal atresia (HP:0002023): Congenital absence of the anus, i.e., the opening at the bottom end of the intestinal tract. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Aganglionic megacolon (HP:0002251): An abnormality resulting from a lack of intestinal ganglion cells (i.e., an aganglionic section of bowel) that results in bowel obstruction with enlargement of the colon. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Celiac disease (HP:0002608): Celiac disease (CD) is an autoimmune condition affecting the small intestine, triggered by the ingestion of gluten, the protein fraction of wheat, barley, and rye. Clinical manifestations of CD are highly variable and include both gastrointestinal and non-gastrointestinal features. The hallmark of CD is an immune-mediated enteropathy. This term is included because the occurrence of CD is seen as a feature of a number of other diseases. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Delayed skeletal maturation (HP:0002750): A decreased rate of skeletal maturation. Delayed skeletal maturation can be diagnosed on the basis of an estimation of the bone age from radiographs of specific bones in the human body. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Atlantoaxial dislocation (HP:0003414): Partial dislocation of the atlantoaxial joint. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Type II diabetes mellitus (HP:0005978): A type of diabetes mellitus initially characterized by insulin resistance and hyperinsulinemia and subsequently by glucose interolerance and hyperglycemia. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Acute megakaryocytic leukemia (HP:0006733): A rare subtype of acute myeloid leukemia evolving from primitive megakaryoblasts. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Impaired pain sensation (HP:0007328): Reduced ability to perceive painful stimuli. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Sparse hair (HP:0008070): Reduced density of hairs. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Renal hypoplasia/aplasia (HP:0008678): Absence or underdevelopment of the kidney. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Chronic constipation (HP:0012450): Constipation for longer than three months with fewer than 3 bowel movements per week, straining, lumpy or hard stools, and a sensation of anorectal obstruction or incomplete defecation. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:870)
- Hyperthyroidism (HP:0000836): An abnormality of thyroid physiology characterized by excessive secretion of the thyroid hormones thyroxine (i.e., T4) and/or 3,3',5-triiodo-L-thyronine zwitterion (i.e., triiodothyronine or T3). Evidence: TAS. Frequency: Very rare (HP:0040284). (ORPHA:870)