Phenotypes associated with the disease Down syndrome (OMIM:190685):
- 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: IEA. Frequency: 298/524. (OMIM:190685)
- Anal atresia (HP:0002023): Congenital absence of the anus, i.e., the opening at the bottom end of the intestinal tract. Evidence: IEA. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- Protruding tongue (HP:0010808): Tongue extending beyond the alveolar ridges or teeth at rest. Evidence: PCS. Frequency: 157/524. (PMID:15036797)
- 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: 400/524. (OMIM:190685)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 17/524. (PMID:15036797)
- Single transverse palmar crease (HP:0000954): The distal and proximal transverse palmar creases are merged into a single transverse palmar crease. Evidence: PCS. Frequency: 184/534. (PMID:15036797;OMIM:190685)
- Prenatal double bubble sign (HP:0025656): Sonographic detection of a double bubble sign in the upper abdomen is strongly indicative of duodenal obstruction. One bubble represents fetal stomach, and the other is attributed to a dilated proximal part of the duodenum; continuity between both bubbles is required for the sign. Evidence: PCS. (PMID:31167209)
- Sporadic (HP:0003745): Cases of the disease in question occur without a previous family history, i.e., as isolated cases without being transmitted from a parent and without other siblings being affected. Evidence: IEA. (OMIM:190685)
- Macroglossia (HP:0000158): Increased length and width of the tongue. Evidence: IEA. (OMIM:190685)
- Patent ductus arteriosus (HP:0001643): In utero, the ductus arteriosus (DA) serves to divert ventricular output away from the lungs and toward the placenta by connecting the main pulmonary artery to the descending aorta. A patent ductus arteriosus (PDA) in the first 3 days of life is a physiologic shunt in healthy term and preterm newborn infants, and normally is substantially closed within about 24 hours after bith and completely closed after about three weeks. Failure of physiologcal closure is referred to a persistent or patent ductus arteriosus (PDA). Depending on the degree of left-to-right shunting, PDA can have clinical consequences. Evidence: PCS. Frequency: 11/58. (PMID:15036797)
- Broad palm (HP:0001169): For children from birth to 4 years of age the palm width is more than 2 SD above the mean; for children from 4 to 16 years of age the palm width is above the 95th centile; or, the width of the palm appears disproportionately wide for the length. Evidence: TAS. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- Ebstein anomaly of the tricuspid valve (HP:0010316): Ebstein's anomaly refers to an abnormally placed and deformed tricuspid valve characterized by apical displacement of the septal and posterior tricuspid valve leaflets, leading to atrialization of the right ventricle with a variable degree of malformation and displacement of the anterior leaflet. Evidence: PCS. Frequency: 1/58. (PMID:15036797)
- 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: IEA. (OMIM:190685)
- Sandal gap (HP:0001852): A widely spaced gap between the first toe (the great toe) and the second toe. Evidence: IEA. Frequency: 242/524. (PMID:15036797)
- Hypoplastic iliac wing (HP:0002866): Underdevelopment of the ilium ala. Evidence: IEA. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- Patent foramen ovale (HP:0001655): Failure of the foramen ovale to seal postnatally, leaving a potential conduit between the left and right cardiac atria. Evidence: PCS. Frequency: 5/58. (PMID:15036797)
- 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: PCS. Frequency: 440/524. (PMID:15036797)
- Congenital onset (HP:0003577): A phenotypic abnormality that is present at birth. Evidence: PCS. (PMID:15036797)
- Complete atrioventricular canal defect (HP:0001674): A congenital heart defect characterized by a specific combination of heart defects with a common atrioventricular valve, primum atrial septal defect and inlet ventricular septal defect. Evidence: IEA. (OMIM:190685)
- 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: PCS. Frequency: 58/524. (PMID:15036797)
- Short middle phalanx of the 5th finger (HP:0004220): Hypoplastic/small middle phalanx of the fifth finger. Evidence: IEA. (OMIM:190685)
- Flat face (HP:0012368): Absence of concavity or convexity of the face when viewed in profile. Evidence: TAS. (OMIM:190685)
- 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: 27/58. (PMID:15036797)
- Microtia (HP:0008551): Underdevelopment of the external ear. Evidence: IEA. (OMIM:190685)
- Duodenal stenosis (HP:0100867): The narrowing or partial blockage of a portion of the duodenum. Evidence: IEA. (OMIM:190685)
- Atrioventricular canal defect (HP:0006695): A defect of the atrioventricular septum of the heart. Evidence: PCS. Frequency: 2/58. (PMID:15036797)
- Clinodactyly (HP:0030084): An angulation of a digit at an interphalangeal joint in the plane of the palm (finger) or sole (toe). Evidence: PCS. Frequency: 189/524. (PMID:15036797)
- Redundant neck skin (HP:0005989): Excess skin around the neck, often lying in horizontal folds. Evidence: PCS. Frequency: 193/524. (PMID:15036797)
- 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: IEA. (OMIM:190685)
- Acute megakaryocytic leukemia (HP:0006733): A rare subtype of acute myeloid leukemia evolving from primitive megakaryoblasts. Evidence: IEA. (OMIM:190685)
- Pulmonary artery stenosis (HP:0004415): An abnormal narrowing or constriction of the pulmonary artery, in the main pulmonary artery and/or in the left or right pulmonary artery branches. Evidence: PCS. Frequency: 4/58. (PMID:15036797)
- Myeloproliferative disorder (HP:0005547): Proliferation (excess production) of hemopoietically active tissue or of tissue which has embryonic hemopoietic potential. Evidence: IEA. (OMIM:190685)
- Brushfield spots (HP:0001088): The presence of whitish spots in a ring-like arrangement at the periphery of the iris. Evidence: PCS. Frequency: 17/524. (PMID:15036797)
- Atlantoaxial instability (HP:0003467): Abnormally increased movement at the junction between the first cervical (atlas) and the second cervical (axis) vertebrae as a result of either a bony or ligamentous anomaly. Evidence: IEA. (OMIM:190685)
- Short palm (HP:0004279): Short palm. Evidence: TAS. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- 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: IEA. (OMIM:190685)
- Partial anomalous pulmonary venous return (HP:0010773): A form of anomalous pulmonary venous return in which not all pulmonary veins drain abnormally. Partial anomalous pulmonary venous return frequently involves one or both of the veins from one lung. Evidence: PCS. Frequency: 1/58. (PMID:15036797)
- Shallow acetabular fossae (HP:0003182). Evidence: IEA. (OMIM:190685)
- Double outlet right ventricle (HP:0001719): Double outlet right ventricle (DORV) is a type of ventriculoarterial connection in which both great vessels arise entirely or predominantly from the right ventricle. Evidence: PCS. Frequency: 2/58. (PMID:15036797)
- 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: PCS. Frequency: 9/58. (PMID:15036797)
- Hypothyroidism (HP:0000821): Deficiency of thyroid hormone. Evidence: IEA. (OMIM:190685)
- Abnormal fetal nasal bone visualization (HP:0025705): Abnormal appearance or non-visualization (apparent absence) of the nasal bone of a fetus in first trimester sonographic screening. Assessment of the fetal nasal bone is generally performed at 11-14 weeks gestational age. Evidence: PCS. (PMID:34247811)
- Atrial septal defect (HP:0001631): Atrial septal defect (ASD) is a congenital abnormality of the interatrial septum that enables blood flow between the left and right atria via the interatrial septum. Evidence: PCS. Frequency: 17/58. (PMID:15036797)