Db	Link	Name	Definition	Comment	Is a
HPO	HP:0001290	Generalized hypotonia	"Generalized muscular hypotonia (abnormally low muscle tone)." [HPO:curators]	—	HP:0001252
HPO	HP:0001274	Agenesis of corpus callosum	"Absence of the corpus callosum as a result of the failure of the corpus callosum to develop, which can be the result of a failure in any one of the multiple steps of callosal development including cellular proliferation and migration, axonal growth or glial patterning at the midline." [HPO:curators]	—	HP:0007370
HPO	HP:0001252	Hypotonia	"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." [HPO:probinson, PMID:21418198]	Hypotonia can be caused by abnormalities of the central nervous system, any element of the motor unit (including the lower motoneuron), or both. Hypotonia is not a specific diagnosis, but can be observed in hundreds of genetic and other diseases. The first distinction to make when assessing a child with hypotonia is whether decreased muscle tone is a result of an abnormality of the central nervous system (CNS), peripheral neuromuscular system, or a combined abnormality involving both. Clinical findings suggestive of an abnormality of the CNS may include hyperreflexia, cognitive developmental delay, and seizures. In contrast, physical findings pointing towards a neuromuscular origin may include weakness, lack of antigravity movements, muscle atrophy, fasciculations, and/or diminished reflexes, most often in the context of normal cognitive function. The HPO term does not distinguish between these etiologies. Additional HPO terms should be used as required to describe associated features.	HP:0003808
HPO	HP:0000262	Turricephaly	"Tall head relative to width and length." [PMID:19125436]	Turricephaly is derived from the Latin word turris, meaning tall, and refers to a round, tall (tower-like) skull. This feature may have previously been considered to overlap with or include a tall forehead. Turricephaly is present when the head appears tall (subjective) and head length and width are reduced compared to normal age-related standards (objective). Head length is measured between the glabella (the most prominent point on the frontal bone above the root of the nose) and the most prominent part of the occiput in the midline, using spreading calipers. Head width is measured between the most lateral points of the parietal bones on each side of the head, using spreading calipers. The term acrocephaly (or oxycephaly) is used when there is turricephaly and the top of the skull assumes a cone shape.	HP:0002648
HPO	HP:0002650	Scoliosis	"The presence of an abnormal lateral curvature of the spine." [HPO:probinson]	—	HP:0010674
HPO	HP:0001357	Plagiocephaly	"Asymmetric head shape, which is usually a combination of unilateral occipital flattening with ipsilateral frontal prominence, leading to rhomboid cranial shape." [PMID:19125436]	Plagiocephaly may affect the posterior skull alone. With plagiocephaly, one can see a combination of unilateral occipital flattening with ipsilateral frontal prominence, leading to rhomboid cranial shape or asymmetry of the posterior skull alone.	HP:0002648
HPO	HP:0000294	Low anterior hairline	"Distance between the hairline (trichion) and the glabella (the most prominent point on the frontal bone above the root of the nose), in the midline, more than two SD below the mean. Alternatively, an apparently decreased distance between the hairline and the glabella." [PMID:19125436]	This feature gives the appearance of a short forehead. It is distinct from hirsutism of the forehead. In the latter, orientation of hair growth is lateral and texture and density of hair differs from scalp hair.	HP:0000599
HPO	HP:0001272	Cerebellar atrophy	"Cerebellar atrophy is defined as a cerebellum with initially normal structures, in a posterior fossa with normal size, which displays enlarged fissures (interfolial spaces) in comparison to the foliae secondary to loss of tissue. Cerebellar atrophy implies irreversible loss of tissue and result from an ongoing progressive disease until a final stage is reached or a single injury, e.g. an intoxication or infectious event." [HPO:probinson, PMID:12169461, PMID:26331051]	Cerebellar atrophy can be diagnosed if the cerebellum is small with shrunken folia and large cerebellar fissures or if it has been shown to undergo progressive volume loss.	HP:0001317
HPO	HP:0001156	Brachydactyly	"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." [HPO:probinson]	—	HP:0011927
HPO	HP:0000316	Hypertelorism	"Interpupillary distance more than 2 SD above the mean (alternatively, the appearance of an increased interpupillary distance or widely spaced eyes)." [PMID:19125427]	—	HP:0100886
HPO	HP:0000520	Proptosis	"An eye that is protruding anterior to the plane of the face to a greater extent than is typical." [HPO:sdoelken, PMID:19125427]	Some sources define "exophthalmos" as a protrusion of the globe greater than 18 mm and "proptosis" as a protusion equal to or less than 18 mm. Others define "exophthalmos" as protusion secondary to endocrine dysfunction and "proptosis" as any non-endocrine-mediated protusion (Source: Wikipedia). This finding should be distinguished frm underdevelopment of the supraorbital ridge or maxilla/zygoma. In proptosis, the globe is anteriorly protuberant to the overall plane of the face.	HP:0100886
HPO	HP:0001249	Intellectual disability	"Subnormal intellectual functioning which originates during the developmental period. Intellectual disability, previously referred to as mental retardation, has been defined as an IQ score below 70." [HPO:probinson]	This term should be used for children at least five years old. For younger children, consider the term Global developmental delay (HP:0001263).	HP:0011446, HP:0012759
HPO	HP:0011800	Midface retrusion	"Posterior positions and/or vertical shortening of the infraorbital and perialar regions, or increased concavity of the face and/or reduced nasolabial angle." [DDD:jclayton-smith, PMID:19125436]	—	HP:0000309
HPO	HP:0000337	Broad forehead	"Width of the forehead or distance between the frontotemporales is more than two standard deviations above the mean (objective); or apparently increased distance between the two sides of the forehead." [PMID:19125436]	Frontotemporalis is a point lateral to the vertical component of the supraorbital ridge, where there is a hollowing. Spreading caliper tips are placed in the deepest part of that hollow. Note that this term should not be confused with prominent forehead.	HP:0000290
HPO	HP:0000365	Hearing impairment	"A decreased magnitude of the sensory perception of sound." [HPO:probinson]	Hearing loss can be categorized by which part of the auditory system is damaged, as conductive hearing loss, sensorineural hearing loss, and mixed hearing loss. Another axis of classification uses the degree of hearing impairment. The degree of hearing loss is computed by using a three frequency average taken at 500 Hz, 1,000 Hz and 2,000 Hz. The average of these three frequencies is called the Pure Tone Average (PTA). 0-20 dB is considered normal, 21-40 dB mild loss, 41-60 dB moderate loss, 61-70 dB moderately severe loss,71-90 dB severe loss, and greater than 90 dB profound loss. Note that the word deafness is occasionally used to describe partial hearing loss. The World Health Organization uses the word deafness to refer to complete loss of the ability to hear, and hearing impairment to refer to any degree of reduced hearing.	HP:0000364
HPO	HP:0009701	Metacarpal synostosis	"Fusion involving two or more metacarpal bones (A synostosis of the first metacarpal and the proximal phalanx of the thumb can also be observed, note that the first metacarpal bone corresponds to a proximal phalanx)." [HPO:probinson]	—	HP:0004278, HP:0005916, HP:0100265
HPO	HP:0000248	Brachycephaly	"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." [HPO:probinson, PMID:19125436]	Cephalic index is the ratio of head width expressed as a percentage of head length. The normal range is 76-80.9%. Head length is measured between the glabella (the most prominent point on the frontal bone above the root of the nose) and the most prominent part of the occiput in the midline, using spreading calipers. Head width is measured between the most lateral points of the parietal bones on each side of the head, using spreading calipers. Cephalic index standards are derived from Caucasians and have limited relevance for other races and ethnicities. Current norms also have limited validity because of changes in infant sleeping position and consequent changes in head shape. New data should be developed. Brachycephaly is distinct from Flat occiput, but both can be present in the same individual and should be coded separately.	HP:0002648
HPO	HP:0002516	Increased intracranial pressure	"An increase of the pressure inside the cranium (skull) and thereby in the brain tissue and cerebrospinal fluid." [HPO:probinson]	Normal values of intracranial pressure in adults are around 7-15 mm Hg in the supine position. The term pseudotumor cerebri (also: idiopathic intracranial hypertension or benign intracranial hypertension) is the presence of increased intracranial pressure in the absence of a brain tumor or other identifiable cause. It should be coded using this term and negations of appropriate other HPO terms. Increased intracranial pressure can damage tissue, contribute to hydrocephalus, cause brain herniation, and restrict blood supply to the brain.	HP:0012640
HPO	HP:0009891	Underdeveloped supraorbital ridges	"Flatness of the supraorbital portion of the frontal bones." [HPO:curators, PMID:19125436]	—	HP:0100538
HPO	HP:0002308	Arnold-Chiari malformation	"Arnold-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." [HPO:curators]	—	HP:0002438
HPO	HP:0002516	Increased intracranial pressure	"An increase of the pressure inside the cranium (skull) and thereby in the brain tissue and cerebrospinal fluid." [HPO:probinson]	Normal values of intracranial pressure in adults are around 7-15 mm Hg in the supine position. The term pseudotumor cerebri (also: idiopathic intracranial hypertension or benign intracranial hypertension) is the presence of increased intracranial pressure in the absence of a brain tumor or other identifiable cause. It should be coded using this term and negations of appropriate other HPO terms. Increased intracranial pressure can damage tissue, contribute to hydrocephalus, cause brain herniation, and restrict blood supply to the brain.	HP:0012640
HPO	HP:0004443	Lambdoidal craniosynostosis	"A kind of craniosynostosis affecting the lambdoidal suture." [HPO:probinson]	—	HP:0001363
HPO	HP:0004440	Coronal craniosynostosis	"Premature closure of the coronal suture of skull." [HPO:probinson]	—	HP:0001363
HPO	HP:0000263	Oxycephaly	"Oxycephaly (from Greek oxus, sharp, and kephalos, head) refers to a conical or pointed shape of the skull." [HPO:curators]	—	HP:0000262
HPO	HP:0001085	Papilledema	"Papilledema refers to edema (swelling) of the optic disc secondary to any factor which increases cerebral spinal fluid pressure." [HPO:probinson]	The borders of the optic disc are normally clear and well defined upon fundoscopic examination. Papilledema is optic disc swelling that can lead to the blurring of optic margins and elevation of optic disc.	HP:0012795