Db	Link	Name	Definition	Comment	Is a
HPO	HP:0001263	Global developmental delay	"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." [DDD:hvfirth, HPO:sdoelken]	Developmental retardation is any significant lag in development in the any or all of the physical, cognitive, behavioral, emotional, or social spheres. Note that the term intellectual disability (mental retardation) refers to not merely a delay in development but rather a permanent limitation. Note that the term 'psychomotor retardation' is also used in some contexts to refer to a slowing of thought and physical movements as a result of major depression or intoxication.	HP:0012758
HPO	HP:0000324	Facial asymmetry	"An abnormal difference between the left and right sides of the face." [HPO:probinson]	—	HP:0001999
HPO	HP:0000256	Macrocephaly	"Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium." [PMID:19125436]	Macrocephaly can be due to hydrocephalus (increased CFSF), megalencephaly (increased brain volume) or thickening of the skull. Head circumference is measured from just above the glabella (the most prominent point on the frontal bone above the root of the nose) to the most posterior prominent point of the occipital bone using a tape measure. Some standard charts are organized by centiles [Hall et al. [2007]], others by standard deviations [Farkas, [1981]]. It is important to add an indication of how far above the normal standard the head circumference is if an accurate assessment of this can be made. Macrocephaly is an absolute term. The term relative macrocephaly can be used when the head size centile exceeds the centile for height, for example, head size at the 75th centile with height at the 5th centile for age and sex.	HP:0040194
HPO	HP:0002007	Frontal bossing	"Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline." [PMID:19125436]	This is not the same as prominent forehead.	HP:0000290, HP:0011218
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: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:0001123	Visual field defect	—	—	HP:0000505
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:0000486	Strabismus	"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." [HPO:probinson, PMID:26319345, UManchester:psergouniotis]	—	HP:0000549
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:0000270	Delayed cranial suture closure	"Infants normally have two fontanels at birth, the diamond-shaped anterior fontanelle at the junction of the coronal and sagittal sutures, and the posterior fontanelle at the intersection of the occipital and parietal bones. The posterior fontanelle usually closes by the 8th week of life, and the anterior fontanel closes by the 18th month of life on average. This term applies if there is delay of closure of the fontanelles beyond the normal age." [HPO:probinson]	—	HP:0011329
HPO	HP:0001305	Dandy-Walker malformation	"A congenital brain malformation typically characterized by incomplete formation of the cerebellar vermis, dilation of the fourth ventricle, and enlargement of the posterior fossa. In layman's terms, Dandy Walker malformation is a cyst in the cerebellum (typically symmetrical) that is involved with the fourth ventricle. This may interfere with the ability to drain cerebrospinal fluid from the brain, resulting in hydrocephalus. Dandy Walker cysts are formed during early embryonic development, while the brain forms. The cyst in the cerebellum typically has several blood vessels running through it connecting to the brain, thereby prohibiting surgical removal." [HPO:probinson, PMID:26246090]	—	HP:0001320, HP:0002198, HP:0002350, HP:0005445
HPO	HP:0000508	Ptosis	"The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective)." [PMID:19125427]	—	HP:0012373
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: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:0003298	Spina bifida occulta	"The closed form of spina bifida with incomplete closure of a vertebral body with intact overlying skin." [HPO:probinson]	May be asymptomatic.	HP:0002414
HPO	HP:0000006	Autosomal dominant inheritance	"A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in heterozygotes. In the context of medical genetics, an autosomal dominant disorder is caused when a single copy of the mutant allele is present. Males and females are affected equally, and can both transmit the disorder with a risk of 50% for each child of inheriting the mutant allele." [HPO:curators]	—	HP:0000005
HPO	HP:0000407	Sensorineural hearing impairment	"A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve." [HPO:probinson]	Hearing loss caused by damage or dysfunction of the auditory nerve (cranial nerve VIII, also known as the cochlear nerve).	HP:0000365, HP:0011389
HPO	HP:0001263	Global developmental delay	"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." [DDD:hvfirth, HPO:sdoelken]	Developmental retardation is any significant lag in development in the any or all of the physical, cognitive, behavioral, emotional, or social spheres. Note that the term intellectual disability (mental retardation) refers to not merely a delay in development but rather a permanent limitation. Note that the term 'psychomotor retardation' is also used in some contexts to refer to a slowing of thought and physical movements as a result of major depression or intoxication.	HP:0012758
HPO	HP:0001290	Generalized hypotonia	"Generalized muscular hypotonia (abnormally low muscle tone)." [HPO:curators]	—	HP:0001252
HPO	HP:0000486	Strabismus	"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." [HPO:probinson, PMID:26319345, UManchester:psergouniotis]	—	HP:0000549
HPO	HP:0001363	Craniosynostosis	"Craniosynostosis refers to the premature closure of the cranial sutures. Primary craniosynostosis refers to the closure of one or more sutures due to abnormalities in skull development, and secondary craniosynostosis results from failure of brain growth." [HPO:probinson]	Skull deformity caused by the premature closure of the cranial sutures. Craniostenosis is a deformity of the skull caused by craniosynostosis, with consequent cessation of skull growth.	HP:0002648, HP:0011329
HPO	HP:0000252	Microcephaly	"Head circumference below 2 standard deviations below the mean for age and gender." [PMID:15806441, PMID:19125436, PMID:25465325, PMID:9683597]	Head circumference is measured from just above the glabella (the most prominent point on the frontal bone above the root of the nose) to the most posterior prominent point of the occipital bone using a tape measure. Some standard charts are organized by centiles, others by standard deviations. It is important to add an indication of how far below the normal standard the head circumference is if an accurate assessment of this can be made. Microcephaly is an absolute term. The term relative microcephaly can be used when the head size centile is less than the centile for height, for example, head size at the 3rd centile with height at the 75% for age and sex. On prenatal ultrasound, microcephaly is diagnosed if the head circumference or the biparietal diameter is more than three standard deviations below the mean. Microcephaly is divided into primary microcephaly, which is present at birth, and secondary microcephaly, which develops postnatally. The crucial difference between these groupings is that primary microcephaly is usually a static developmental anomaly, whereas secondary microcephaly indicates a progressive neurodegenerative condition	HP:0007364, HP:0040195
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:0000348	High forehead	"An abnormally increased height of the forehead." [HPO:probinson]	—	HP:0000290