- Progressive microcephaly (HP:0000253): Progressive microcephaly is diagnosed when the head circumference falls progressively behind age- and gender-dependent norms. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:477814)
- Hypoplastic optic chiasm (HP:0034311): Developmental defect characterized by undergrowth of the optic chiasm. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:477814)
- 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: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:477814)
- Profound intellectual disability (HP:0002187): Profound intellectual disability (ID) is defined as a type of ID characterized by profoundly sub-average adaptive functioning and intellectual functioning, with an intelligence quotient (IQ) below 20. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:477814)
- Cerebral visual impairment (HP:0100704): A form of loss of vision caused by damage to the visual cortex rather than a defect in the eye. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:477814)
- Recurrent infections (HP:0002719): Increased susceptibility to infections as manifested by repeated bouts of infection. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:477814)
- 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: TAS. Frequency: Frequent (HP:0040282). (ORPHA:477814)
- Decreased body weight (HP:0004325): Abnormally low body weight. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:477814)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Delayed puberty (HP:0000823): Passing the age when puberty normally occurs with no physical or hormonal signs of the onset of puberty. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Failure to thrive in infancy (HP:0001531). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Bronchiectasis (HP:0002110): Persistent abnormal dilatation of the bronchi owing to localized and irreversible destruction and widening of the large airways. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Lymphoma (HP:0002665): A cancer originating in lymphocytes and presenting as a solid tumor of lymhpoid cells. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Skeletal muscle atrophy (HP:0003202): The presence of skeletal muscular atrophy (which is also known as amyotrophy). Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Combined immunodeficiency (HP:0005387): A group of phenotypically heterogeneous genetic disorders characterized by profound deficiencies of T- and B-cell function, which predispose the patients to both infectious and noninfectious complications. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Metopic synostosis (HP:0011330): Premature fusion of the metopic suture. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- B-cell lymphoma (HP:0012191): A type of lymphoma that originates in B-cells. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Brain atrophy (HP:0012444): Partial or complete wasting (loss) of brain tissue that was once present. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- Decreased total CD4+ T cell proportion (HP:0032218): Abnormal decrease of helper CD3+CD4+ T cells, measured as percentage of total CD3+ T cells in the blood, compared to a reference range for a given sex and age-group. These are usually measured within the TCR alpha/beta positive population. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
- 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: TAS. Frequency: Occasional (HP:0040283). (ORPHA:477814)
These phenotypes are associated with the disease Progressive microcephaly-seizures-cortical blindness-developmental delay syndrome (ORPHA:477814).