- Nyctalopia (HP:0000662): Inability to see well at night or in poor light. Evidence: PCS. (PMID:9326941)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. (PMID:9326941)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. (PMID:9326941)
- Severely reduced visual acuity (HP:0001141): Severe reduction of the ability to see. On the 6m visual acuity scale, severe reduction is defined as less than 6/60 but at least 3/60. On the 20ft visual acuity scale, severe reduction is defined as less than 20/200 but at least 20/400. On the decimal visual acuity scale, severe reduction is defined as less than 0.1 but at least 0.05. Evidence: PCS. (PMID:9326941)
- 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:9326941)
- Visual impairment (HP:0000505): Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery. Evidence: PCS. (PMID:9326941)
- Rod-cone dystrophy (HP:0000510): An inherited retinal disease subtype in which the rod photoreceptors appear to be more severely affected than the cone photoreceptors. Typical presentation is with nyctalopia (due to rod dysfunction) followed by loss of mid-peripheral field of vision, which gradually extends and leaves many patients with a small central island of vision due to the preservation of macular cones. Evidence: PCS. (PMID:9326941)
- Attenuation of retinal blood vessels (HP:0007843): Narrowing of the retinal blood vessels, both arterioles and venules. Evidence: PCS. (PMID:9326941)
These phenotypes are associated with the disease retinitis pigmentosa 20 (OMIM:613794).