- Poor speech (HP:0002465). Evidence: PCS. Frequency: 4/6. (PMID:24115387)
- 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: 4/6. (PMID:24115387)
- Long face (HP:0000276): Facial height (length) is more than 2 standard deviations above the mean (objective); or, an apparent increase in the height (length) of the face (subjective). Evidence: PCS. Frequency: 4/6. (PMID:24115387)
- Seizure (HP:0001250): A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain. Evidence: PCS. Frequency: 3/6. (PMID:24115387)
- 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: 6/6. (PMID:24115387)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. (PMID:24115387)
- X-linked recessive inheritance (HP:0001419): A mode of inheritance that is observed for recessive traits related to a gene encoded on the X chromosome. In the context of medical genetics, X-linked recessive disorders manifest in males (who have one copy of the X chromosome and are thus hemizygotes), but generally not in female heterozygotes who have one mutant and one normal allele. Evidence: PCS. (PMID:24115387)
- Optic atrophy (HP:0000648): Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy. Evidence: PCS. Frequency: 1/6. (PMID:24115387)
- Clinodactyly (HP:0030084): An angulation of a digit at an interphalangeal joint in the plane of the palm (finger) or sole (toe). Evidence: PCS. Frequency: 1/6. (PMID:24115387)
- Unilateral ptosis (HP:0007687): A unilateral form of ptosis. Evidence: PCS. Frequency: 1/6. (PMID:24115387)
- Macrotia (HP:0000400): Median longitudinal ear length greater than two standard deviations above the mean and median ear width greater than two standard deviations above the mean (objective); or, apparent increase in length and width of the pinna (subjective). Evidence: PCS. Frequency: 2/6. (PMID:24115387)
- Hyperactivity (HP:0000752): Hyperactivity is a condition characterized by constant and unusually high levels of activity, even in situations where it is deemed inappropriate. Evidence: PCS. Frequency: 6/6. (PMID:24115387)
- 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: 1/6. (PMID:24115387)
- 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: 6/6. (PMID:24115387)
These phenotypes are associated with the disease intellectual disability, X-linked 101 (OMIM:300928).