- Hypermelanotic macule (HP:0001034): A hyperpigmented circumscribed area of change in normal skin color without elevation or depression of any size. Evidence: PCS. Frequency: 1/1. (PMID:36866916)
- Melanoma (HP:0002861): The presence of a melanoma, a malignant cancer originating from pigment producing melanocytes. Melanoma can originate from the skin or the pigmented layers of the eye (the uvea). Evidence: IEA. (OMIM:278700)
- Defective DNA repair after ultraviolet radiation damage (HP:0003079). Evidence: IEA. (OMIM:278700)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: IEA. (OMIM:278700)
- Telangiectasia (HP:0001009): Telangiectasias refer to small dilated blood vessels located near the surface of the skin or mucous membranes, measuring between 0.5 and 1 millimeter in diameter. Telangiectasia are located especially on the tongue, lips, palate, fingers, face, conjunctiva, trunk, nail beds, and fingertips. Evidence: IEA. (OMIM:278700)
- Distal sensory impairment (HP:0002936): An abnormal reduction in sensation in the distal portions of the extremities. Evidence: PCS. Frequency: 1/1. (PMID:34484303)
- Ectropion (HP:0000656): An outward turning (eversion) or rotation of the eyelid margin. Evidence: IEA. (OMIM:278700)
- Mental deterioration (HP:0001268): Loss of previously present mental abilities, generally in adults. Evidence: IEA. Frequency: 1/1. (OMIM:278700)
- 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. (OMIM:278700)
- Poikiloderma (HP:0001029): Poikiloderma refers to a patch of skin with (1) reticulated hypopigmentation and hyperpigmentation, (2) wrinkling secondary to epidermal atrophy, and (3) telangiectasias. Evidence: IEA. (OMIM:278700)
- Neonatal onset (HP:0003623): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 1/1. (PMID:36866916)
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: IEA. (OMIM:278700)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 1/1. (PMID:34484303)
- Microcephaly (HP:0000252): Head circumference below 2 standard deviations below the mean for age and gender. Evidence: IEA. (OMIM:278700)
- Cutaneous photosensitivity (HP:0000992): An increased sensitivity of the skin to light. Photosensitivity may result in a rash upon exposure to the sun (which is known as photodermatosis). Photosensitivity can be diagnosed by phototests in which light is shone on small areas of skin. Evidence: PCS. Frequency: 1/1. (PMID:36866916)
- Dermal atrophy (HP:0004334): Partial or complete wasting (atrophy) of the skin. Evidence: IEA. (OMIM:278700)
- Choreoathetosis (HP:0001266): Involuntary movements characterized by both athetosis (inability to sustain muscles in a fixed position) and chorea (widespread jerky arrhythmic movements). Evidence: IEA. (OMIM:278700)
- Pes cavus (HP:0001761): An increase in height of the medial longitudinal arch of the foot that does not flatten on weight bearing (i.e., a distinctly hollow form of the sole of the foot when it is bearing weight). Evidence: PCS. Frequency: 1/1. (PMID:34484303)
- Keratitis (HP:0000491): Inflammation of the cornea. Evidence: IEA. (OMIM:278700)
- Squamous cell carcinoma of the skin (HP:0006739): Squamous cell carcinoma of the skin is a malignant tumor of squamous epithelium. Evidence: PCS. Frequency: 1/1. (PMID:36866916)
- Sensorineural hearing impairment (HP:0000407): A type of hearing impairment in one or both ears related to an abnormal functionality of the cochlear nerve. Evidence: IEA. (OMIM:278700)
- Verrucous epidermal nevus (HP:0034275): A type of epidermal nevus (which represent Blaschkoid hamartomas of the skin that result from mosaic post-zygotic mutations) that appears as skin-colored-to-brown, sharply demarcated, papillomatous papules that coalesce into plaques. The majority of these nevi are either present at birth or occur within the first year of life. Evidence: PCS. Frequency: 1/1. (PMID:34484303)
- Conjunctivitis (HP:0000509): Inflammation of the conjunctiva. Evidence: IEA. (OMIM:278700)
- 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:2234061)
- Erythematous papule (HP:0030350): A circumscribed, solid elevation of skin with no visible fluid that is reddish (erythematous) in color. Evidence: PCS. Frequency: 1/1. (PMID:36866916)
- Spasticity (HP:0001257): A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes. Evidence: IEA. (OMIM:278700)
- Entropion (HP:0000621): An abnormal inversion (turning inward) of the eyelid (usually the lower) towards the globe. Entropion is usually acquired as a result of involutional or cicatricial processes but may occasionally be congenital. Evidence: IEA. (OMIM:278700)
These phenotypes are associated with the disease xeroderma pigmentosum group A (OMIM:278700).