ADIPOR1

ADIPOR1 provides the instructions for making a protein called adiponectin receptor 1. This protein normally receives signals from adiponectin, a hormone released by fat tissue that helps regulate how the body handles fats and sugar. When adiponectin binds to this receptor, it activates a signaling pathway that influences fat breakdown and insulin sensitivity. In the eye, laboratory and animal studies suggest the receptor also helps the retina take up and keep an omega-3 fatty acid called docosahexaenoic acid (DHA), which photoreceptor (definition: A light-sensing cell in the retina. Rods (used for night and peripheral vision) and cones (used for color and detail) are the two types.) cells need to function. It is important to understand that a report of a change in this gene does not automatically mean it is the cause of a person's vision problem, because the human evidence connecting ADIPOR1 to retinal disease is still limited to a few reports.

In the small number of human reports available, changes in ADIPOR1 have been associated with retinitis pigmentosa, a group of conditions in which the light-sensing cells of the retina gradually stop working. One report described a person with a syndromic form of retinitis pigmentosa, meaning retinal disease occurring alongside other body-wide features. A separate report described a large family with a non-syndromic (eye-only) form of retinitis pigmentosa that appeared to be passed down in a dominant pattern. These two reports describe different inheritance patterns and different accompanying features, so it is not yet clear what a single, consistent ADIPOR1-related eye condition looks like. Symptoms described in retinitis pigmentosa can include night blindness, narrowing of the side (peripheral) vision, and reduced sharpness of vision, but how or whether these apply to any individual with an ADIPOR1 change cannot be predicted from the current evidence. A separate line of research has also examined ADIPOR1 gene variation as a possible risk factor for age-related macular degeneration, which is a different condition from retinitis pigmentosa.

The normal biological role of the ADIPOR1 protein as an adiponectin receptor involved in fat and sugar metabolism is well characterized. Laboratory and mouse studies consistently show that removing AdipoR1 function reduces retinal DHA, disturbs fatty-acid balance, and leads to progressive degeneration of photoreceptors with reduced electrical responses in the retina. Mouse studies have also linked AdipoR1 loss to a buildup of a lipid called ceramide, and reducing ceramide in those mice helped protect photoreceptors and improve retinal function. Research also shows that ADIPOR1 works closely with another retinal protein called MFRP, which helps organize the surface of the retinal pigment epithelium.

The central uncertainty is that only a small number of human reports connect ADIPOR1 to inherited retinal disease, so its role as a genuine disease-causing gene is not established. The available human reports disagree on important points, describing both a recessive syndromic form and a dominant eye-only form, which leaves the inheritance pattern and expected features unclear. ADIPOR1 is not covered in GeneReviews, and RP Hope's reviewers have flagged the overall evidence for a retinal-disease link as limited. The reported association with age-related macular degeneration comes from a single population study and describes a modest statistical risk, not a direct cause. The promising treatment ideas, such as lowering ceramide, come from mouse and cell studies and have not been shown to be safe or effective in people with ADIPOR1-related eye disease.

RP Hope's reviewed records do not currently identify a gene-specific approved treatment for ADIPOR1-related retinal disease. Much of the current research is laboratory-based and focuses on understanding how loss of the AdipoR1 protein disturbs fatty-acid and ceramide balance in the retina. In mouse studies, lowering ceramide levels with experimental drugs protected photoreceptors and improved measures of retinal function, but these are animal findings and not a treatment available to patients. Other laboratory work has explored an adiponectin-based peptide and an AdipoR1 agonist compound in the context of age-related macular degeneration and retinal aging in animals, which again represents early research rather than proven therapy. None of these approaches has been shown in the supplied evidence to be safe or effective in people with ADIPOR1-related retinal disease.

• ADIPOR1 change reported in a person with syndromic retinitis pigmentosa

  Single human case with supporting laboratory work (case report).

  What was found:

  They identified a homozygous frameshift change in ADIPOR1 and noted the person's features resembled those of AdipoR1-deficient mice, which show retinal dystrophy, obesity, and behavioral abnormalities.

  Why it matters:

  This was among the first reports proposing ADIPOR1 as a disease gene for a retinal condition in humans.

  Limitation: Evidence rests on one case, so it cannot establish how often or how consistently ADIPOR1 causes disease.

• ADIPOR1 change reported in a family with dominant retinitis pigmentosa

  Single-family human study with laboratory and animal support.

  What was found:

  A heterozygous ADIPOR1 change (p.Y310C) tracked with disease in the family, affected protein folding and localization in cells, and reducing adipor1 in zebrafish preferentially reduced rod photoreceptors.

  Why it matters:

  It offered a second, independent human link between ADIPOR1 and retinitis pigmentosa, this time in a non-syndromic, dominant form.

  Limitation: One family described a dominant eye-only pattern that differs from the earlier recessive syndromic report, leaving the true disease mechanism unresolved.

• AdipoR1 conserves DHA and supports photoreceptor survival in mice

  Animal and laboratory (preclinical mechanism) research.

  What was found:

  Loss of AdipoR1 reduced retinal DHA, lowered specialized photoreceptor lipids, severely weakened retinal electrical responses, and led to progressive photoreceptor degeneration.

  Why it matters:

  It established a plausible biological role for AdipoR1 in maintaining photoreceptors, helping explain why the gene is a candidate for retinal disease.

  Limitation: Findings are in mice and cells and do not by themselves prove the same process causes disease in people.

• Lowering ceramide protects photoreceptors in AdipoR1-deficient mice

  Animal (preclinical) treatment research.

  What was found:

  AdipoR1-deficient retinas accumulated ceramide, and drug treatment that lowered ceramide protected photoreceptors and improved cone-related retinal function and some visual responses.

  Why it matters:

  It provides a proof-of-concept therapeutic idea for ADIPOR1-related retinopathy that researchers may build on.

  Limitation: This is an experimental strategy in mice and is not an available or proven treatment for people.

• ADIPOR1 variant and age-related macular degeneration risk in a Finnish population

  Observational human genetic association study.

  What was found:

  One intronic ADIPOR1 variant was modestly associated with AMD status, with a risk allele that was fairly common in the group studied.

  Why it matters:

  It suggests ADIPOR1 variation might contribute to AMD risk, a condition distinct from retinitis pigmentosa.

  Limitation: A modest statistical association in a single population is not proof of cause and applies to AMD, not to inherited retinitis pigmentosa.

A helpful first step for caregivers is to ask the person what type of assistance they would prefer, rather than assuming help is needed for every task. Because inherited retinal conditions can affect side vision and vision in low light, low-vision rehabilitation and accessible technology may support independence for those who need them. Family members who have questions about their own risk may find genetic counseling useful, especially given how uncertain the ADIPOR1 evidence currently is. RP Hope's patient and family stories can offer emotional and community support for people navigating a new diagnosis. RP Hope's My RP Pathway tool can help families find practical resources on topics such as accommodations and support.

• Given how limited the human evidence is for ADIPOR1, how confident can we be that this gene explains my vision changes?
• Does my genetic report describe a variant that has been clearly linked to disease, or one of uncertain significance?
• Would additional testing or evaluation help clarify whether my diagnosis is retinitis pigmentosa, age-related macular degeneration, or another condition?
• What inheritance pattern, if any, applies to my situation, and what could that mean for my family?
• What kind of monitoring of my vision would you recommend over time?
• Are there low-vision or supportive services you would suggest now, regardless of the exact genetic cause?

Because the evidence linking ADIPOR1 to retinal disease is limited, discussing your specific genetic report with a retinal specialist or genetic counselor can help clarify what it means for you. A genetic counselor can explain how confidently a particular ADIPOR1 finding can be tied to symptoms and whether additional testing may be useful. RP Hope's genetic testing resource outlines why testing matters and offers questions to bring to that conversation. RP Hope's My RP Pathway tool can guide you and your family to relevant resources at whatever stage you are in. If you want to understand research activity, RP Hope's Clinical Trials Finder lets you screen for studies rather than relying on this page to determine eligibility.