- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- 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: PCS. Frequency: 1/2. (PMID:35325049)
- Antenatal onset (HP:0030674): Onset prior to birth. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Cerebellar atrophy (HP:0001272): 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. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Glossoptosis (HP:0000162): Posterior displacement of the tongue into the pharynx, i.e., a tongue that is mislocalised posteriorly. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Small epiphyses (HP:0010585): Reduction in the size or volume of epiphyses. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Flat face (HP:0012368): Absence of concavity or convexity of the face when viewed in profile. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- 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: 1/2. (PMID:35325049)
- Hypoplastic cervical vertebrae (HP:0008434). Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Leukodystrophy (HP:0002415): Leukodystrophy refers to deterioration of white matter of the brain resulting from degeneration of myelin sheaths in the CNS. Their basic defect is directly related to the synthesis and maintenance of myelin membranes. Symmetric white matter involvement at MRI is a typical finding in patients with leukodystrophies. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Retrognathia (HP:0000278): An abnormality in which the mandible is mislocalised posteriorly. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Knee dislocation (HP:0004976). Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Short long bone (HP:0003026): One or more abnormally short long bone. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Cerebral atrophy (HP:0002059): Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- 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: PCS. Frequency: 1/2. (PMID:35325049)
- Absent speech (HP:0001344): Complete lack of development of speech and language abilities. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Scoliosis (HP:0002650): The presence of an abnormal lateral curvature of the spine. Evidence: PCS. Frequency: 2/2. (PMID:35325049)
- Coxa valga (HP:0002673): Coxa valga is a deformity of the hip in which the angle between the femoral shaft and the femoral neck is increased compared to age-adjusted values (about 150 degrees in newborns gradually reducing to 120-130 degrees in adults). Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Hypoplasia of the corpus callosum (HP:0002079): Underdevelopment of the corpus callosum. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Advanced ossification of carpal bones (HP:0004233): Ossification of carpal bones at an abnormally early age. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Feeding difficulties (HP:0011968): Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Joint hypermobility (HP:0001382): The capability that a joint (or a group of joints) has to move, passively and/or actively, beyond normal limits along physiological axes. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Limb dystonia (HP:0002451): A type of dystonia (abnormally increased muscular tone causing fixed abnormal postures) that affects muscles of the limbs. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Elbow dislocation (HP:0003042): Dislocation of the distal humerus out of the elbow joint, where the radius, ulna, and humerus meet. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- 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: 2/2. (PMID:35325049)
- Adducted thumb (HP:0001181): In the resting position, the tip of the thumb is on, or near, the palm, close to the base of the fourth or fifth finger. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- 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:35325049)
- Lumbar scoliosis (HP:0004626). Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Pierre-Robin sequence (HP:0000201): Pierre Robin malformation is a sequence of developmental malformations characterized by micrognathia (mandibular hypoplasia), glossoptosis and cleft palate. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
- Horizontal nystagmus (HP:0000666): Nystagmus consisting of horizontal to-and-fro eye movements. Evidence: PCS. Frequency: 1/2. (PMID:35325049)
These phenotypes are associated with the disease leukodystrophy, hypomyelinating, 26, with chondrodysplasia (OMIM:620269).