$Unique_ID{BRK03967} $Pretitle{} $Title{Marcus Gunn Phenomenon} $Subject{Marcus Gunn Phenomenon Jaw-winking Maxillopalpebral Synkinesis Marcus Gunn Ptosis with jaw-winking Marcus Gunn Syndrome Facial Nerve Injury Marin-Amat Syndrome Inverse Marcus Gunn Phenomenon Oral-Facial-Digital Syndrome Faciopalpebral Synkinesis } $Volume{} $Log{} Copyright (C) 1991 National Organization for Rare Disorders, Inc. 833: Marcus Gunn Phenomenon ** IMPORTANT ** It is possible that the main title of the article (Marcus Gunn Phenomenon) is not the name you expected. Please check the SYNONYM listing to find the alternate names and disorder subdivisions covered by this article. Synonyms Jaw-winking Maxillopalpebral Synkinesis Marcus Gunn Ptosis (with jaw-winking) Marcus Gunn (Jaw-Winking) Syndrome Information on the following disorders can be found in the Related Disorders section of this report: Facial Nerve Injury Marin-Amat Syndrome (Inverse Marcus Gunn Phenomenon) Oral-Facial-Digital Syndrome Faciopalpebral Synkinesis General Discussion ** REMINDER ** The information contained in the Rare Disease Database is provided for educational purposes only. It should not be used for diagnostic or treatment purposes. If you wish to obtain more information about this disorder, please contact your personal physician and/or the agencies listed in the "Resources" section of this report. Marcus Gunn Phenomenon is a rare genetic disorder that is usually present at birth. Major symptoms include the upper eyelid of one eye raising rapidly upon movement of the jaw. This disorder can be corrected with surgery. Symptoms The upper eyelid of one eye droops in most patients with Marcus Gunn Phenomenon. The major symptom of this disorder is that upon movement of the lower jaw, the eyelid of the affected eye involuntarily and rapidly raises, causing the eye to open wider. This first becomes apparent soon after the baby is born when, during feeding, sucking causes the eyelid to move up and down. In some patients, one eye may be either crossed or looking away; i.e., deviates in a different direction from the normal eye (strabismus), or one eye may have better sight than the other. Other eye problems (anisometropia, superior rectus muscle palsy) may also be present. Causes Marcus Gunn Phenomenon may be inherited as an autosomal dominant trait. Human traits, including the classic genetic diseases, are the product of the interaction of two genes, one received from the father and one from the mother. In dominant disorders a single copy of the disease gene (received from either the mother or father) will be expressed "dominating" the other normal gene and resulting in appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is fifty percent for each pregnancy regardless of the sex of the resulting child. Affected Population Marcus Gunn Phenomenon is a rare genetic disorder present at birth. It affects males and females in equal numbers. Related Disorders Marcus Gunn Phenomenon may occur in conjunction with certain other eye disorders such as Duane Syndrome, or possibly Retinitis Pigmentosa. (For more information on these disorders, choose "Duane," or "Retinitis Pigmentosa" as your search term in the Rare Disease Database). Certain types of injury to the facial nerve may produce symptoms similar to Marcus Gunn Phenomenon. Marin-Amat Syndrome is similar to Marcus Gunn Phenomenon except that the eye closes, rather than opens wider, when the jaw moves to open the mouth. This disorder is also referred to as "Inverse Marcus Gunn Phenomenon." Oral-Facial-Digital Syndrome is a rare genetic disorder. In patients with Type III of this syndrome, upon movement of the lower jaw the eyelid involuntarily and rapidly raises, causing the eye to open wider (jaw- winking). More than the normal number of teeth are usually present. Other major symptoms may include disturbances involving the nervous and muscle (neuromuscular) systems, congenital (present at birth) malformations such as cleft palate, other facial deformities, malformation of the hands and feet, shortened limbs and various degrees of mental retardation. (For more information on this disorder, choose "Oral-Facial-Digital" as your search term in the Rare Disease Database). Faciopalpebral Synkinesis is a rare disorder characterized by the upper eyelid of one eye raising when the individual smiles. Therapies: Standard Surgery can correct the eyelid abnormalities of Marcus Gunn Phenomenon. Genetic counseling may be of benefit for patients and their families. Other related eye problems such as strabismus, amblyopia, etc., can be corrected with eyeglasses, surgery and/or drugs. Therapies: Investigational Scientists are trying to identify the gene that causes Marcus Gunn Phenomenon. Research and genetic studies are ongoing. This disease entry is based upon medical information available through June 1991. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder. Resources For more information on Marcus Gunn Phenomenon, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 NIH/National Eye Institute 9000 Rockville Pike Bethesda, MD 20892 (301) 496-5248 For genetic information and genetic counseling referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10605 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References MENDELIAN INHERITANCE IN MAN, 9th Ed.: Victor A. McKusick; Johns Hopkins University Press, 1990. Pp. 599. AUDITORY BRAIN-STEM RESPONSES IN MARCUS GUNN PTOSIS. D. J. Creel, et al.; Electroencephalogr Clin Neurophysiol (Jul 1984; issue 59 (4)). Pp. 341- 344. LEVATOR SLING FOR MARCUS GUNN PTOSIS. S. M. Betharia and S. Kumar; Br J Ophthalmol (Sep 1987; issue 71 (9)). Pp. 685-689. THE MARCUS GUNN PHENOMENON. A REVIEW OF 71 CASES. S. G. Pratt, et al.; Ophthalmology (Jan 1984; issue 91 (1)). Pp. 27-30.