- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Kyphoscoliosis (HP:0002751): An abnormal curvature of the spine in both a coronal (lateral) and sagittal (back-to-front) plane. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Parakeratosis (HP:0001036): Abnormal formation of the keratinocytes of the epidermis characterized by persistence of nuclei, incomplete formation of keratin, and moistness and swelling of the keratinocytes. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- 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: 1/1. (PMID:30239721)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Secondary microcephaly (HP:0005484): Head circumference which falls below 2 standard deviations below the mean for age and gender because of insufficient head growth after birth. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Subcutaneous nodule (HP:0001482): Slightly elevated lesions on or in the skin with a diameter of over 5 mm. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Reduced eye contact (HP:0000817): A reduced frequency or duration of eye contact. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Self-injurious behavior (HP:0100716): Self-aggression. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- Agitation (HP:0000713): A state of excessive motor activity that is associated with mental distress or a feeling of substantial unease or inner tension. Distinguished from restlessness by the increased level of emotional distress and negative intensity of the experience. Agitation has a significant level of physical activity that is typically threatening to the self or others. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
- 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:30239721)
- Hyperkeratosis (HP:0000962): Hyperkeratosis is a histopathological term defining a thickened stratum corneum and may be present in many different skin conditions, with many possible overlaps. Hyperkeratosis refers to the increased thickness of the stratum corneum, the outer layer of the skin. Hyperkeratosis is subclassified as orthokeratotic or parakeratotic. Orthokeratotic hyperkeratosis refers to the thickening of the keratin layer with preserved keratinocyte maturation, while parakeratotic hyperkeratosis shows retained nuclei as a sign of delayed maturation of keratinocytes. Evidence: PCS. Frequency: 1/1. (PMID:30239721)
These phenotypes are associated with the disease infantile cataract, skin abnormalities, glutamate excess, and impaired intellectual development (OMIM:618339).