- Astigmatism (HP:0000483): A type of refraction error associated with abnormal curvatures on the anterior and/or posterior surface of the cornea. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Strabismus (HP:0000486): 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. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Hypermetropia (HP:0000540): An abnormality of refraction characterized by the ability to see objects in the distance clearly, while objects nearby appear blurry. Evidence: PCS. Frequency: 3/3. (PMID:27005418)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Spastic gait (HP:0002064): Spasticity is manifested by increased stretch reflex which is intensified with movement velocity. This results in excessive and inappropriate muscle activation which can contribute to muscle hypertonia. Spastic gait is characterized by manifestations such as muscle hypertonia, stiff knee, and circumduction of the leg. Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- Optic nerve dysplasia (HP:0001093): The presence of developmental dysplasia of the optic nerve. Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- Dilated third ventricle (HP:0007082): An increase in size of the third ventricle. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 3/3. (PMID:27005418)
- Prominent forehead (HP:0011220): Forward prominence of the entire forehead, due to protrusion of the frontal bone. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Fetal onset (HP:0011461): Onset prior to birth but after 8 weeks of embryonic development (corresponding to a gestational age of 10 weeks). Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Reduced visual acuity (HP:0007663). Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Dental crowding (HP:0000678): Changes in alignment of teeth in the dental arch. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Lower limb hypertonia (HP:0006895). Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- 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: 3/3. (PMID:27005418)
- Hyperreflexia (HP:0001347): Hyperreflexia is the presence of hyperactive stretch reflexes of the muscles. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Lateral ventricle dilatation (HP:0006956). Evidence: PCS. Frequency: 3/3. Onset: Fetal onset (HP:0011461). (PMID:27005418)
- Polyhydramnios (HP:0001561): The presence of excess amniotic fluid in the uterus during pregnancy. Evidence: PCS. Frequency: 1/2. Onset: Fetal onset (HP:0011461). (PMID:27005418)
- 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:29667355;PMID:27005418)
- Full cheeks (HP:0000293): Increased prominence or roundness of soft tissues between zygomata and mandible. Evidence: PCS. Frequency: 2/4. (PMID:29667355;PMID:27005418)
- Delayed ability to stand (HP:0025335): A failure to achieve the ability to stand up at an appropriate developmental stage. Most children begin to walk alone at 11 to 15 months of age. On average, children can stand while holding on at the age of 9 to 10 months, can pull up to stand and walk with one hand being held at 12 months, and can stand alone and walk well at 18 months. Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- Deeply set eye (HP:0000490): An eye that is more deeply recessed into the plane of the face than is typical. Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- 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: PCS. Frequency: 4/4. (PMID:29667355;PMID:27005418)
- Limb hypertonia (HP:0002509). Evidence: PCS. Frequency: 2/3. (PMID:27005418)
- Partial agenesis of the corpus callosum (HP:0001338): A partial failure of the development of the corpus callosum. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Tip-toe gait (HP:0030051): An abnormal gait pattern characterized by the failure of the heel to contact the floor at the onset of stance during gait. Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- Esotropia (HP:0000565): A form of strabismus with one or both eyes turned inward ('crossed') to a relatively severe degree, usually defined as 10 diopters or more. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Spastic paraplegia (HP:0001258): Complete loss of the ability to move the lower limbs accompanied by spasticity of the lower limbs. Evidence: PCS. Frequency: 3/3. (PMID:27005418)
- Plagiocephaly (HP:0001357): Asymmetric head shape, which is usually a combination of unilateral occipital flattening with ipsilateral frontal prominence, leading to rhomboid cranial shape. Evidence: PCS. Frequency: 3/3. (PMID:27005418)
- Frontal bossing (HP:0002007): Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline. Evidence: PCS. Frequency: 1/3. (PMID:27005418)
- Short philtrum (HP:0000322): Distance between nasal base and midline upper lip vermilion border more than 2 SD below the mean. Alternatively, an apparently decreased distance between nasal base and midline upper lip vermilion border. Evidence: PCS. Frequency: 1/1. (PMID:29667355)
- Autosomal dominant inheritance (HP:0000006): 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. Evidence: PCS. (PMID:27005418)
- Obesity (HP:0001513): Accumulation of substantial excess body fat. Evidence: PCS. Frequency: 3/4. (PMID:29667355;PMID:27005418)
- 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: PCS. Frequency: 3/3. (PMID:27005418)
These phenotypes are associated with the disease spastic paraplegia, intellectual disability, nystagmus, and obesity (OMIM:617296).