$Unique_ID{BRK04078} $Pretitle{} $Title{Pallister-Killian Mosaic Syndrome} $Subject{Pallister-Killian Mosaic Syndrome Chromosome 12, Isochromosome 12p Mosaicism Killian Syndrome Killian/Teschler-Nicola Syndrome Pallister Mosaic Syndrome Pallister Mosaic Syndrome Tetrasomy 12p Teschler-Nicola/Killian Syndrome Chromosome 12, Partial Trisomy 12P Hypomelanosis of ITO} $Volume{} $Log{} Copyright (C) 1992 National Organization for Rare Disorders, Inc. 512: Pallister-Killian Mosaic Syndrome ** IMPORTANT ** It is possible that the main title of the article (Pallister-Killian Mosaic Syndrome) is not the name you expected. Please check the SYNONYMS listing to find the alternate name and disorder subdivisions covered by this article. Synonyms Chromosome 12, Isochromosome 12p Mosaicism Killian Syndrome Killian/Teschler-Nicola Syndrome Pallister Mosaic Syndrome Pallister Mosaic Syndrome Tetrasomy 12p Teschler-Nicola/Killian Syndrome Information on the following diseases can be found in the Related Disorders section of this report: Chromosome 12, Partial Trisomy 12P Hypomelanosis of ITO 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. Pallister-Killian Mosaic Syndrome is a rare chromosomal disorder that occurs for no apparent reason. Major symptoms may include a coarse face with a high forehead, sparse hair on the scalp, an abnormally wide space between the eyes, a fold of the skin over the inner corner of the eyes, and a broad nasal bridge with a highly arched palate. Mental retardation, loss of muscle tone, and streaks of skin lacking color are often present. Symptoms Patients with Pallister-Killian Mosaic Syndrome typically have low muscle tone at birth, sparse scalp hair, a high forehead, a coarse face, an abnormally wide space between the eyes, a broad nasal bridge, a highly arched palate, a fold of the skin over the inner corner of the eyes, and large ears with lobes that are thick and protrude outward. Other features frequently found in patients with this disorder may include: streaks of skin in which there is no color (hypopigmentation), extra nipples, seizures, droopy upper eyelids, crossed eyes (strabismus), joints that will not move (contractures), and delays in perceiving, recognizing, judging, sensing, reasoning or imagining (cognitive delays). Congenital heart defects, hernia's of the diaphragm, a narrowing of the external auditory canal (stenosis) and an abnormal opening in the anus have also been associated with Pallister-Killian Mosaic Syndrome. Causes Pallister-Killian Mosaic Syndrome is caused by tetrasomy for chromosome 12p. Patients with Pallister-Killian Mosaic Syndrome have four copies of the short arm of chromosome 12 instead of the normal two. All recorded cases of this disorder have been sporadic (not believed to be hereditary). Affected Population Pallister-Killian Mosaic Syndrome is a very rare disorder that affects males and females in equal numbers. There have been approximately 30 cases of this disorder reported in the medical literature. Related Disorders Symptoms of the following disorders can be similar to those of Pallister- Killian Mosaic Syndrome. Comparisons may be useful for a differential diagnosis: Hypomelanosis of ITO is a rare disorder in which the main characteristic is lesions of the skin. A whorl-like lack of pigmentation of the skin may occur on any part of the body except the soles, palms, and scalp. Over half of the patients with this disorder may have seizures, mental retardation, crossed eyes, nearsightedness, a cleft along the edge of the eyeball (coloboma), an abnormally small head and/or an abnormal overgrowth of brain tissue (megalencephaly). Autosomal dominant inheritance has been suggested in some cases. Chromosome 12, Partial Trisomy 12P, is a rare genetic disorder in which there is a triplicated section of the short arm of the 12th chromosome. Patients with this disorder have a lack of muscle tone (hypotonia), growth retardation, and distinct facial features such as a flat upturned nose with a wide bridge, shallow eye sockets, a vertical fold of the skin over the inner corner of the eye, an upward slant of the opening between the upper and lower eyelids, a long thick lower lip, a large tongue and short broad hands with the fifth finger bent to the side. Chromosome 12, Partial Trisomy 12P affects females twice as often as males. Therapies: Standard Pallister-Killian Mosaic Syndrome can be diagnosed prenatally by removing a small amount of fluid that is in the womb during pregnancy (amniocentesis), or by studying the cell parts that concern heredity, especially chromosomes (cytogenetic) in bone marrow. Children with Pallister-Killian Mosaic Syndrome may benefit from early intervention programs and special education. Genetic counseling may be of benefit for patients and their families. Other treatment is symptomatic and supportive. Therapies: Investigational Research on birth defects and their causes is ongoing. The National Institutes of Health (NIH) is sponsoring the Human Genome Project which is aimed at mapping every gene in the human body and learning why they sometimes malfunction. It is hoped that this new knowledge will lead to prevention and treatment of birth defects in the future. This disease entry is based upon medical information available through March 1992. 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 Pallister-Killian Syndrome, please contact: National Organization for Rare Disorders (NORD) P.O. Box 8923 New Fairfield, CT 06812-1783 (203) 746-6518 Pallister-Killian Family Support Group 4255 5th Ave., SW Naples, FL 33999 (813) 455-0400 Association for Retarded Citizens of the U.S. P.O. Box 6109 Arlington, TX 76005 (817) 640-0204 1-800-433-5255 For Genetic Information and Genetic Counseling Referrals: March of Dimes Birth Defects Foundation 1275 Mamaroneck Avenue White Plains, NY 10505 (914) 428-7100 Alliance of Genetic Support Groups 35 Wisconsin Circle, Suite 440 Chevy Chase, MD 20815 (800) 336-GENE (301) 652-5553 References SMITH'S RECOGNIZABLE PATTERNS OF HUMAN MALFORMATION, 4th Ed.: Kenneth L. Jones, M.D., Editor; W. B. Saunders Co., 1988. Pp. 176. BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief; Blackwell Scientific Publications, 1990. Pp. 1353. PRENATAL DIAGNOSIS OF PALLISTER-KILLIAN SYNDROME: S. Soukup, et al.; Am J Med Genet (April, 1990, issue 35(4)). Pp. 526-8. MOSAICISM IN PALLISTER i(12p) SYNDROME: S.L. Wenger, et al.; Am J Med Genet (April, 1990, issue 35(4)). Pp. 523-5. PALLISTER-KILLIAN MOSAIC SYNDROME WITH EMPHASIS ON THE ADULT PHENOTYPE: O.W. Quarrell, et al.; Am J Med Genet (December, 1988, issue 31(4)). Pp. 841-4. ISOCHROMOSOME 12p MOSAICISM (PALLISTER-KILLIAN SYNDROME): NEWBORN DIAGNOSIS BY DIRECT BONE MARROW ANALYSIS: B.E. Ward, et al.; Am J Genet (December, 1988, issue 31(4)). Pp. 835-9. SKELETAL ANOMALIES IN A PATIENT WITH THE PALLISTER/TESCHLER- NICOLA/KILLIAN SYNDROME: H Kawashima; Am J Med Genet (June, 1987, issue 28(2)). Pp. 285-9.