- 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: Very frequent (HP:0040281). (ORPHA:3380)
- 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: Very frequent (HP:0040281). (ORPHA:3380)
- Dolichocephaly (HP:0000268): An abnormality of skull shape characterized by a increased anterior-posterior diameter, i.e., an increased antero-posterior dimension of the skull. Cephalic index less than 76%. Alternatively, an apparently increased antero-posterior length of the head compared to width. Often due to premature closure of the sagittal suture. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Prominent occiput (HP:0000269): Increased convexity of the occiput (posterior part of the skull). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Microretrognathia (HP:0000308): A form of developmental hypoplasia of the mandible in which the mandible is mislocalised posteriorly. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Hypertelorism (HP:0000316): Interpupillary distance more than 2 SD above the mean (alternatively, the appearance of an increased interpupillary distance or widely spaced eyes). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Triangular face (HP:0000325): Facial contour, as viewed from the front, triangular in shape, with breadth at the temples and tapering to a narrow chin. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- 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:3380)
- 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:3380)
- Hypertonia (HP:0001276): A condition in which there is increased muscle tone so that arms or legs, for example, are stiff and difficult to move. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Growth delay (HP:0001510): A deficiency or slowing down of growth pre- and postnatally. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Intrauterine growth retardation (HP:0001511): An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Omphalocele (HP:0001539): A midline anterior incomplete closure of the abdominal wall in which there is herniation of the abdominal viscera into the base of the abdominal cord. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- 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: Very frequent (HP:0040281). (ORPHA:3380)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Narrow pelvis bone (HP:0003275): Reduced side to side width of the pelvis. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Deviation of finger (HP:0004097): Deviated fingers is a term that should be used if one or more fingers of the hand are deviated from their normal position, either to the radial or ulnar side. A deviation of a finger can be caused by an abnormal form of one or more of the phalanges of the affected finger, or by a deviation or displacement of one or more phalanges. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- 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:3380)
- Cachexia (HP:0004326): Severe weight loss, wasting of muscle, loss of appetite, and general debility related to a chronic disease. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- 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: Very frequent (HP:0040281). (ORPHA:3380)
- Abnormal cardiovascular system morphology (HP:0030680): Any structural anomaly of the heart and blood vessels. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Camptodactyly of finger (HP:0100490): The distal interphalangeal joint and/or the proximal interphalangeal joint of the fingers cannot be extended to 180 degrees by either active or passive extension. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Cognitive impairment (HP:0100543): Abnormal cognition is characterized by deficits in thinking, reasoning, or remembering. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Pointed helix (HP:0100810). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
- Abnormal morphology of female internal genitalia (HP:0000008): An abnormality of the female internal genitalia. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Horseshoe kidney (HP:0000085): A connection of the right and left kidney by an isthmus of functioning renal parenchyma or fibrous tissue that crosses the midline. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Hydronephrosis (HP:0000126): Severe distention of the kidney with dilation of the renal pelvis and calices. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Cleft palate (HP:0000175): Cleft palate is a developmental defect of the palate resulting from a failure of fusion of the palatine processes and manifesting as a separation of the roof of the mouth (soft and hard palate). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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:3380)
- 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: Frequent (HP:0040282). (ORPHA:3380)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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: Frequent (HP:0040282). (ORPHA:3380)
- Choanal atresia (HP:0000453): Absence or abnormal closure of the choana (the posterior nasal aperture). Most embryologists believe that posterior choanal atresia results from a failure of rupture between the 35th and 38th day of fetal life of the partition which separates the bucconasal or buccopharyngeal membranes. The resultant choanal atresia may be unilateral or bilateral, bony or membranous, complete or incomplete. In over 90 per cent of cases the obstruction is bony, while in the remainder it is membranous. The bony type of atresia is commonly located 1-2 mm. anterior to the posterior edge of the hard palate, and the osseous septum varies in thickness from 1 to 10 mm. In the membranous form of choanal atresia the obstruction usually occurs further posteriorly. In approximately one third of cases the atresia is bilateral. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Blepharophimosis (HP:0000581): A fixed reduction in the vertical distance between the upper and lower eyelids with short palpebral fissures. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Congenital diaphragmatic hernia (HP:0000776): The presence of a hernia of the diaphragm present at birth. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Single umbilical artery (HP:0001195): Single umbilical artery (SUA) is the absence of one of the two umbilical arteries surrounding the fetal bladder and in the fetal umbilical cord. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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:3380)
- Polyhydramnios (HP:0001561): The presence of excess amniotic fluid in the uterus during pregnancy. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Talipes equinovarus (HP:0001762): Talipes equinovarus (also called clubfoot) typically has four main components: inversion and adduction of the forefoot; inversion of the heel and hindfoot; equinus (limitation of extension) of the ankle and subtalar joint; and internal rotation of the leg. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Small nail (HP:0001792): A nail that is diminished in length and width, i.e., underdeveloped nail. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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: Frequent (HP:0040282). (ORPHA:3380)
- Anal atresia (HP:0002023): Congenital absence of the anus, i.e., the opening at the bottom end of the intestinal tract. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Esophageal atresia (HP:0002032): A developmental defect resulting in complete obliteration of the lumen of the esophagus such that the esophagus ends in a blind pouch rather than connecting to the stomach. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Choroid plexus cyst (HP:0002190): A cyst occurring within the choroid plexus within a cerebral ventricle. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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: Frequent (HP:0040282). (ORPHA:3380)
- Central apnea (HP:0002871): Apnea resulting from depression of the respiratory centers in the medulla oblongata. There is a lack of respiratory effort rather than obstruction of airflow. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Abnormal hip bone morphology (HP:0003272): An abnormality of the hip bone. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Hypoplasia of the nasal bone (HP:0004646): Underdevelopment of the nasal bone. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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:3380)
- Feeding difficulties in infancy (HP:0008872): Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Overlapping fingers (HP:0010557): A finger resting on the dorsal surface of an adjacent digit when the hand is at rest. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Increased nuchal translucency (HP:0010880): Nuchal translucency is the sonographic appearance of subcutaneous accumulation of liquid in the back of the fetal neck in the first trimester of pregnancy (11-14 gestational weeks of pregnancy). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Abnormality of the upper urinary tract (HP:0010935): An abnormality of the upper urinary tract. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Non-midline cleft of the upper lip (HP:0100335): Clefting (gap or groove) of the upper lip affecting the lateral portions of the upper lip rather than the midline/median region. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- Hernia (HP:0100790). Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:3380)
- 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:3380)
- Microphthalmia (HP:0000568): A developmental anomaly characterized by abnormal smallness of one or both eyes. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Iris coloboma (HP:0000612): A coloboma of the iris. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Abnormal rib morphology (HP:0000772): An anomaly of the rib. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Short sternum (HP:0000879): Decreased inferosuperior length of the sternum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Hand clenching (HP:0001188): An abnormal hand posture in which the hands are clenched to fists. All digits held completely flexed at the metacarpophalangeal and interphalangeal joints. In prenatal sonography of the fetal clenched hand, the index finger overlaps a clenched fist formed by the other digits. The proximal interphalangeal articulation of the index finger is flexed and ulnarly deviated, and the thumb is adducted. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Cerebellar hypoplasia (HP:0001321): Cerebellar hypoplasia is a descriptive term implying a cerebellum with a reduced volume, but a normal shape and is stable over time. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Holoprosencephaly (HP:0001360): Holoprosencephaly is a structural anomaly of the brain in which the developing forebrain fails to divide into two separate hemispheres and ventricles. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Pyloric stenosis (HP:0002021): Pyloric stenosis, also known as infantile hypertrophic pyloric stenosis, is an uncommon condition in infants characterized by abnormal thickening of the pylorus muscles in the stomach leading to gastric outlet obstruction. Clinically infants are well at birth. Then, at 3 to 6 weeks of age, the infants present with projectile vomiting, potentially leading to dehydration and weight loss. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Chiari malformation (HP:0002308): Chiari malformation consists of a downward displacement of the cerebellar tonsils and the medulla through the foramen magnum, sometimes causing hydrocephalus as a result of obstruction of CSF outflow. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Anencephaly (HP:0002323): Anencephaly is a developmental anomaly characterized by a fetus that has no calvarium, with a lack of most or all of the fetus' brain tissue. Anencephaly belongs to a collective group known as neural tube defects (NTD) and is a result of the neural tube failing to close in its rostral end during fetal development. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Spina bifida (HP:0002414): Incomplete closure of the embryonic neural tube, whereby some vertebral arches remain unfused and open. The mildest form is spina bifida occulta, followed by meningocele and meningomyelocele. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Abnormality of the lower limb (HP:0002814): An abnormality of the leg. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Abnormality of the upper limb (HP:0002817): An abnormality of the arm. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Aplasia/Hypoplasia of the radius (HP:0006501): A small/hypoplastic or absent/aplastic radius. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Aplasia/Hypoplasia of the corpus callosum (HP:0007370): Absence or underdevelopment of the corpus callosum. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Abnormal retinal pigmentation (HP:0007703): Any deviation from the normal pigmentation of the retina. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Corneal opacity (HP:0007957): A reduction of corneal clarity. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:3380)
- Posteriorly rotated ears (HP:0000358): A type of abnormal location of the ears in which the position of the ears is characterized by posterior rotation (the superior part of the ears is rotated towards the back of the head, and the inferior part of the ears towards the front). Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:3380)
These phenotypes are associated with the disease Trisomy 18 syndrome (ORPHA:3380).