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Disease Profile

Marcus Gunn phenomenon

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

Jaw-winking; Maxillopalpebral synkinesis; Familial Marcus Gunn phenomenon (subtype);


Marcus Gunn phenomenon is a rare condition characterized by movement of the upper eyelid in a rapid rising motion (a "wink") each time the jaw moves.[1] The wink phenomenon may be elicited by opening the mouth, thrusting the jaw to the side, jaw protrusion, chewing, smiling, or sucking.[2] It is usually present at birth and may occur with other eye abnormalities (such as strabismus) or vision problems.[1][2] Although it usually affects one eye, it can affect both eyes in rare cases.[2] The exact cause is not known. Marcus Gunn phenomenon is generally sporadic, but familial cases have been reported.[3][2] Treatment is not always needed but may include surgery in more severe cases.[1]


Signs and symptoms of Marcus Gunn phenomenom (MGP) may include the following:

  • Mild-to-moderate drooping of the eyelids (blepharoptosis), usually on one side (unilateral)
  •  Synkinetic (involuntary) upper eyelid movement after almost any movement of the lower jaw including: mouth opening, chewing, sucking, jaw protrusion, clenching teeth together, and swallowing
  • Worsening of symptoms when looking down
  • Decreased vision due to amblyopia ("lazy eye")
  • Strabismus ("crossed eyes")

These symptoms are usually first noticed in infancy while bottle or breast feeding.[2]

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
Percent of people who have these symptoms is not available through HPO
Autosomal dominant inheritance
Congenital ptosis
Congenital drooping upper eyelid
Unilateral ptosis
Dropping of one upper eyelid


While it may not be needed in every case, people with Marcus Gunn phenomenon may benefit from surgery. Children with Marcus Gunn phenomenon need to be regularly monitored for amblyopia. If not addressed by age 7 to 10 years of age, amblyopia may become untreatable.[10] Untreated severe ptosis can also result in vision loss.[10] Other associated eye problems, such as horizontal strabismus, vertical strabismus, and double elevator palsy typically need to be addressed before considering how to manage Marcus Gunn phenomenon itself.[11] These related eye problems may be corrected with eyeglasses, surgery, and/or medications.[1]

Surgery for Marcus Gunn phenomenon may be considered for ptosis or jaw winking that is considered cosmetically significant, or causing amblyopia. Depending on the degree of ptosis and severity of jaw winking, several surgical techniques have been proposed.[11] For mild Marcus Gunn phenomenon, management has included observation, levator muscle resection, and the Fasanella-Servat procedure.[11]

More detailed information about treatment of Marcus Gunn phenomenon is available on Medscape Reference's Web site and can be viewed here.


Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Social Networking Websites

Learn more

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • EyeWiki is an eye encyclopedia written by eye physicians and surgeons that offers an information page on Marcus Gunn phenomenon. Please click the link to access this resource.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Marcus Gunn phenomenon. Click on the link to view a sample search on this topic.


  1. Marcus Gunn Phenomenon. National Organization for Rare Disorders (NORD). 2003; https://rarediseases.org/rare-diseases/marcus-gunn-phenomenon/.
  2. Sean M Blaydon. Marcus Gunn Jaw-winking Syndrome. Medscape Reference. November 30, 2015; https://emedicine.medscape.com/article/1213228-overview.
  3. Marcus-Gunn syndrome. Orphanet. April 2007; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=EN&Expert=91412.
  4. Conte A, Brancati F, Garaci F, Toschi N, Bologna M, Fabbrini G, Falla M, Dallapiccola B, Bollero P, Floris R, and Berardelli A. Kinematic and Diffusion Tensor Imaging Definition of Familial Marcus Gunn Jaw-Winking Synkinesis. PLoS One. 2012; 7(12):e51749. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3524082.
  5. Kniffin CL. Marcus Gunn Phenomen. OMIM. February 9 2006; https://www.omim.org/entry/154600.
  6. Sundareswaran S, Nipun CA, and Kumar V. Jaw winking phenomenon: Report of a case with review of literature. Indian J Dent Res. May-June 2015; 26(3):320-3. https://www.ncbi.nlm.nih.gov/pubmed/26275203.
  7. Mrabet A, Oueslati S, Gazzah H, and Ben Hamida M. Clinical and electrophysiological study of 2 familial cases of Marcus Gunn phenomenon. Rev Neurol (Paris). 1991; 147(3):215-9. https://www.ncbi.nlm.nih.gov/pubmed/2063068.
  8. Kaçar Bayram A, Per H, Quon J, Canpolat M, Ülgen E, Dogan H, Gumus H, Kumandas S, Bayram N, Bilguvar K, and Çaglayan AO. A rare case of congenital fibrosis of extraocular muscle type 1A due to KIF21A mutation with Marcus Gunn jaw-winking phenomenon. Eur J Paediatr Neurol. November 2015; 19(6):743-6. https://www.ncbi.nlm.nih.gov/pubmed/26190014.
  9. Gupta M, Gupta OP, and Vohra V. Bilateral familial vertical Duane Syndrome with synergistic convergence, aberrant trigeminal innervation, and facial hypoplasia. Oman J Ophthalmol. September 2014; 7(3):135-37. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4220400.
  10. Gomez VMP and Ganatra SR. Marcus-Gunn jaw winking ptosis. EyeWiki: American Academy of Ophthalmology. January 4 2016; https://eyewiki.aao.org/Marcus-Gunn_jaw_winking_ptosis.
  11. Demirci H, Frueh BR, Nelson CC. Marcus Gunn jaw-winking synkinesis: clinical features and management. Ophthalmology. July 2010; 117(7):1447-1452. https://www.ncbi.nlm.nih.gov/pubmed/20188419.

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