- Hypothalamic hamartoma (HP:0002444): The presence of a hamartoma of the hypothalamus. Evidence: PCS. Frequency: 2/5. (PMID:35045343)
- Hearing impairment (HP:0000365): A decreased magnitude of the sensory perception of sound. Evidence: PCS. Frequency: 1/4. (PMID:35045343)
- Retinal coloboma (HP:0000480): A notch or cleft of the retina or choroid, located vertically below the optic disc. Evidence: PCS. Frequency: 1/4. (PMID:35045343)
- Short columella (HP:0002000): Reduced distance from the anterior border of the naris to the subnasale. Evidence: PCS. Frequency: 2/5. (PMID:35045343)
- 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: PCS. Frequency: 1/5. (PMID:35045343)
- Gray matter heterotopia (HP:0002282): Heterotopia or neuronal heterotopia are macroscopic clusters of misplaced neurons (gray matter), most often situated along the ventricular walls or within the subcortical white matter. Evidence: PCS. Frequency: 2/5. (PMID:35045343)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: PCS. Frequency: 4/4. (PMID:35045343)
- Thin corpus callosum (HP:0033725): An abnormally thin corpus callous, due to atrophy, hypoplasia or agenesis. This term is intended to be used in situations where it is not known if thinning of the corpus callosum (for instance, as visualized by magnetic resonance tomography) is due to abnormal development (e.g. a leukodystrophy) or atrophy following normal development (e.g. neurodegeneration). Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Cleft earlobe (HP:0011265): Discontinuity in the convexity of the inferior margin of the lobe. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Ulnar deviation of the hand (HP:0009487): Divergence of the longitudinal axis of the hand at the wrist in a posterior (ulnar) direction (i.e., towards the little finger). Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Genu recurvatum (HP:0002816): An abnormally increased extension of the knee joint, so that the knee can bend backwards. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Microtia (HP:0008551): Underdevelopment of the external ear. Evidence: PCS. Frequency: 2/5. (PMID:35045343)
- 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: PCS. Frequency: 1/5. (PMID:35045343)
- Ventriculomegaly (HP:0002119): An increase in size of the ventricular system of the brain. Evidence: PCS. Frequency: 3/5. (PMID:35045343)
- High palate (HP:0000218): Height of the palate more than 2 SD above the mean (objective) or palatal height at the level of the first permanent molar more than twice the height of the teeth (subjective). Evidence: PCS. Frequency: 1/4. (PMID:35045343)
- Macroglossia (HP:0000158): Increased length and width of the tongue. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Macrocephaly (HP:0000256): Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium. Evidence: PCS. Frequency: 2/6. (PMID:35045343)
- 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: PCS. Frequency: 3/4. (PMID:35045343)
- Cerebellar vermis hypoplasia (HP:0001320): Underdevelopment of the vermis of cerebellum. Evidence: PCS. Frequency: 4/5. (PMID:35045343)
- Highly arched eyebrow (HP:0002553): Increased height of the central portion of the eyebrow, forming a crescent, semicircular, or inverted U shape. Evidence: PCS. Frequency: 2/5. (PMID:35045343)
- Dysphagia (HP:0002015): Difficulty in swallowing. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Delayed speech and language development (HP:0000750): A degree of language development that is significantly below the norm for a child of a specified age. Evidence: PCS. Frequency: 4/4. (PMID:35045343)
- Hamartoma of tongue (HP:0011802): A benign (noncancerous) tumorlike malformation made up of an abnormal mixture of cells and tissues that originates in the tongue. Evidence: PCS. Frequency: 2/6. (PMID:35045343)
- Interhemispheric cyst (HP:0032327): Cystic collection (sac-like, fluid containing pocket of membranous tissue) located in the interhemispheric fissure, with or without communication with the ventricular system. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Broad thumb (HP:0011304): Increased thumb width without increased dorso-ventral dimension. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Reduced social responsiveness (HP:0012760): A reduced ability to participate in the back-and-forth flow of social interaction appropriate to culture and developmental level, which is normally characterized by an influence of the behavior of one person on the behavior of another person. This results in difficulty interacting with others through emotional, physical, or verbal communication. Evidence: PCS. Frequency: 3/4. (PMID:35045343)
- Autosomal recessive inheritance (HP:0000007): 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 individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:35045343)
- Partial agenesis of the corpus callosum (HP:0001338): A partial failure of the development of the corpus callosum. Evidence: PCS. Frequency: 3/5. (PMID:35045343)
- High forehead (HP:0000348): An abnormally increased height of the forehead. Evidence: PCS. Frequency: 2/4. (PMID:35045343)
- Sandal gap (HP:0001852): A widely spaced gap between the first toe (the great toe) and the second toe. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Sacral dimple (HP:0000960): A cutaneous indentation resulting from tethering of the skin to underlying structures (bone) of the intergluteal cleft. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Micrognathia (HP:0000347): Developmental hypoplasia of the mandible. Evidence: PCS. Frequency: 5/6. (PMID:35045343)
- Polymicrogyria (HP:0002126): Polymicrogyria is a congenital malformation of the cerebral cortex characterized by abnormal cortical layering (lamination) and an excessive number of small gyri (folds). Evidence: PCS. Frequency: 3/5. (PMID:35045343)
- Facial asymmetry (HP:0000324): An abnormal difference between the left and right sides of the face. Evidence: PCS. Frequency: 1/5. (PMID:35045343)
- Bilateral talipes equinovarus (HP:0001776): Bilateral clubfoot deformity. Evidence: PCS. Frequency: 1/4. (PMID:35045343)
These phenotypes are associated with the disease congenital disorder of deglycosylation 2 (OMIM:619775).