- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: PCS. Frequency: 7/7. (PMID:19615668)
- Undetectable light-adapted electroretinogram (HP:0030465): No detectable response to the light-adapted 3.0 ERG (single-flash cone response). This type of ERG measures responses of the cone system; a-waves arise from cone photoreceptors and cone off-bipolar cells; the b-wave comes from On- and Off-cone bipolar cells. Evidence: PCS. Frequency: 5/6. (PMID:19615668)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 7/7. (PMID:19615668)
- Photophobia (HP:0000613): Excessive sensitivity to light with the sensation of discomfort or pain in the eyes due to exposure to bright light. Evidence: PCS. Frequency: 5/7. (PMID:19615668)
- 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:19615668)
- Reduced visual acuity (HP:0007663). Evidence: PCS. Frequency: 7/7. (PMID:19615668)
- Dyschromatopsia (HP:0007641): A form of colorblindness in which only two of the three fundamental colors can be distinguished due to a lack of one of the retinal cone pigments. Evidence: PCS. Frequency: 7/7. (PMID:19615668)
- 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:19615668)
- Cone/cone-rod dystrophy (HP:0000548). Evidence: PCS. (PMID:19615668)
- Absent foveal reflex (HP:0030825): Absent reflectivity of the fovea, which normally is a bright pinpoint of light that is observed to move sideways or up and down in response to movement of the opthalmoscope. Evidence: PCS. Frequency: 5/7. (PMID:19615668)
These phenotypes are associated with the disease cone dystrophy 4 (OMIM:613093).