Chromosome 20 trisomy

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U.S. Department of Health & Human Services

Genetic and Rare Diseases Information Center (GARD)

Trisomy chromosome 20
Trisomy 20
Trisomy 20 mosaicism
Mosaic trisomy 20

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Chromosome 20 trisomy
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Chromosome 20, trisomy, (also called trisomy 20) is a condition in which a fetus or individual has an extra full or partial copy of chromosome 20 in some or all of of his/her cells. An extra full copy of chromosome 20 in all of a person's cells is rare, and almost all fetuses with this do not survive past the first trimester of pregnancy.^[3] The presence of an extra copy of only part of chromosome 20 is called partial trisomy 20; and an extra copy of chromosome 20 in only some of a person's cells is called mosaic trisomy 20. Mosaic trisomy 20 is the most common type of chromosome 20 trisomy and is one of the more common chromosomal abnormalities found during prenatal diagnostic testing. Studies have shown that the child is normal in the vast majority of prenatally diagnosed individuals. However, features that have been reported include spinal abnormalities (including spinal stenosis, vertebral fusion, and kyphosis), hypotonia (decreased muscle tone), lifelong constipation, sloped shoulders, and significant learning disabilities despite normal intelligence.^[2] Trisomy 20 usually results from an error that occurs when an egg or sperm cell develops (before fertilization); mosaic trisomy 20 usually results from errors in cell division soon after fertilization.^[1]

More about Chromosome 20 trisomy

References

Chromosome abnormalities. March of Dimes. December 2009 Available at: http://www.marchofdimes.com/Baby/birthdefects_chromosomal.html. Accessed December 17, 2010.
Willis MJ, Bird LM, Dell'Aquilla M, Jones MC. Expanding the phenotype of mosaic trisomy 20. American Journal of Medical Genetics. February 1, 2008;146(3):330-336. Available at: http://www.ncbi.nlm.nih.gov/pubmed/18203170. December 17, 2010.
Mavromatidis G, Dinas K, Delkos D, Vosnakis C, Mamopoulos A, Rousso D. Case of prenatally diagnosed non-mosaic trisomy 20 with minor abnormalities. Journal of Obstetrics and Gynaecology Reearch. August 2010;36(4):866-868. Available at: http://www.ncbi.nlm.nih.gov/pubmed/20666959. December 17, 2010.

Questions & Answers (Found 1 Question)

A list of questions from the public on rare and/or genetic diseases that have been answered by the Genetic and Rare Disease Information Center. Click on each question to find the answer.

Can a person with chromosome 20, trisomy pass this on to his/her children? ( Click here for answer)

For more information about Chromosome 20 trisomy click on the boxes below:

More Detailed Information	Organizations	Services	Scientific Conferences	Clinical Trials & Research


More Detailed Information (Found 2 resources) Links where you can find more general information, comprehensive resources, selected full text journal articles, and news updates. Disclaimer General Genetics Home Reference (GHR) contains information on Chromosome 20 trisomy. Click on the link to go to GHR and review the information. PubMed is a searchable database of medical literature and lists journal articles that discuss Chromosome 20 trisomy. Click on the link to view a sample search on this topic.

More Detailed Information (Found 2 resources)
Links where you can find more general information, comprehensive resources, selected full text journal articles, and news updates. Disclaimer

General
- Genetics Home Reference (GHR) contains information on Chromosome 20 trisomy. Click on the link to go to GHR and review the information.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Chromosome 20 trisomy. Click on the link to view a sample search on this topic.

Organizations Providing General Support \| Social Networking Websites
Organizations (Found 7 resources) Groups providing a wide range of services, supportive resources, and information. Disclaimer Unique – Rare Chromosome Disorder Support Group P.O. Box 2189 Caterham Surrey CR3 5GN United Kingdom Telephone: 440 1883 330766 E-mail: info@rarechromo.org Web site: http://www.rarechromo.org Chromosome Disorder Outreach PO Box 724 Boca Raton, FL 33429 Telephone: 561-395-4252 E-mail: info@chromodisorder.org Web site: http://www.chromodisorder.org Organizations Providing General Support Genetic Alliance 4301 Connecticut Avenue NW Suite 404 Washington, DC 20008-2369 Telephone: 202-966-5557 Fax: 202-966-8553 E-mail: info@geneticalliance.org Web site: http://www.geneticalliance.org National Organization for Rare Disorders (NORD) 55 Kenosia Avenue PO Box 1968 Danbury, CT 06813-1968 Toll-free: 1-800-999-6673 (voicemail only) Telephone: 203-744-0100 TTY: 203-797-9590 Fax: 203-798-2291 E-mail: orphan@rarediseases.org Web site: http://www.rarediseases.org/ Social Networking Websites DNAandU.org is a Web site and blog that collects firsthand stories from people facing issues, making tough decisions, and using genomic (DNA) information in their own healthcare. Click on the link to learn from their experiences and/or submit your own story. Madisons Foundation P.O. Box 241956 Los Angeles, CA 90024 Telephone: 310-264-0826 Fax: 310-264-4766 E-mail: getinfo@madisonsfoundation.org Web site: http://www.madisonsfoundation.org/ RareShare is an online social hub dedicated to patients, families and healthcare professionals affected by rare medical disorders.

Organizations Providing General Support | Social Networking Websites

Organizations (Found 7 resources)
Groups providing a wide range of services, supportive resources, and information. Disclaimer

- Unique – Rare Chromosome Disorder Support Group
  P.O. Box 2189
  Caterham
  Surrey CR3 5GN
  United Kingdom
  Telephone: 440 1883 330766
  E-mail: info@rarechromo.org
  Web site: http://www.rarechromo.org
- Chromosome Disorder Outreach
  PO Box 724
  Boca Raton, FL 33429
  Telephone: 561-395-4252
  E-mail: info@chromodisorder.org
  Web site: http://www.chromodisorder.org
Organizations Providing General Support
- Genetic Alliance
  4301 Connecticut Avenue NW
  Suite 404
  Washington, DC 20008-2369
  Telephone: 202-966-5557
  Fax: 202-966-8553
  E-mail: info@geneticalliance.org
  Web site: http://www.geneticalliance.org
- National Organization for Rare Disorders (NORD)
  55 Kenosia Avenue
  PO Box 1968
  Danbury, CT 06813-1968
  Toll-free: 1-800-999-6673 (voicemail only)
  Telephone: 203-744-0100
  TTY: 203-797-9590
  Fax: 203-798-2291
  E-mail: orphan@rarediseases.org
  Web site: http://www.rarediseases.org/
Social Networking Websites
- DNAandU.org is a Web site and blog that collects firsthand stories from people facing issues, making tough decisions, and using genomic (DNA) information in their own healthcare. Click on the link to learn from their experiences and/or submit your own story.
- Madisons Foundation
  P.O. Box 241956
  Los Angeles, CA 90024
  Telephone: 310-264-0826
  Fax: 310-264-4766
  E-mail: getinfo@madisonsfoundation.org
  Web site: http://www.madisonsfoundation.org/
- RareShare is an online social hub dedicated to patients, families and healthcare professionals affected by rare medical disorders.

Genetic Services \| Parent Resources
Services (Found 3 resources) Links to Web sites that offer services, such as tools to locate specialists, specialty clinics, genetic services, and genetic testing laboratories. Disclaimer Many individuals want to know about healthcare professionals or researchers who have knowledge of their conditions. When a condition is rare, it can be difficult to find someone who has seen many cases. Although there is no list of experts in rare diseases, GARD's How to Find an Expert fact sheet provides several ways to identify healthcare professionals who have experience with a particular condition. Click on the link to access this resource and learn more. Genetic Services You may wish to discuss your concerns with a genetics professional. The following online resources can help you find a genetics professional in your community: GeneTests has a searchable directory of US and international genetics and prenatal diagnosis clinics. The National Society of Genetic Counselors provides a searchable directory of US and international genetic counseling services. The American College of Medical Genetics has a searchable database of US genetics clinics. The University of Kansas Medical Center provides a list of US and international genetic centers, clinics, and departments. The American Society of Human Genetics maintains a database of its members, which includes individuals who live outside of the United States. Visit the link to obtain a list of the geneticists in your country, some of whom may be researchers that do not provide medical care. Parent Resources The Parent Technical Assistance Center Network provides a list of the Parent Training and Information Centers in each state. These centers are funded by the United States Department of Education to provide early intervention and special education information and training to parents of children with disabilities from birth to age 26. Click on the link to find the Parent Center in your state.

Genetic Services | Parent Resources

Services (Found 3 resources)
Links to Web sites that offer services, such as tools to locate specialists, specialty clinics, genetic services, and genetic testing laboratories. Disclaimer

- Many individuals want to know about healthcare professionals or researchers who have knowledge of their conditions. When a condition is rare, it can be difficult to find someone who has seen many cases. Although there is no list of experts in rare diseases, GARD's How to Find an Expert fact sheet provides several ways to identify healthcare professionals who have experience with a particular condition. Click on the link to access this resource and learn more.
Genetic Services
- You may wish to discuss your concerns with a genetics professional. The following online resources can help you find a genetics professional in your community:
  - GeneTests has a searchable directory of US and international genetics and prenatal diagnosis clinics.
  - The National Society of Genetic Counselors provides a searchable directory of US and international genetic counseling services.
  - The American College of Medical Genetics has a searchable database of US genetics clinics.
  - The University of Kansas Medical Center provides a list of US and international genetic centers, clinics, and departments.
  - The American Society of Human Genetics maintains a database of its members, which includes individuals who live outside of the United States. Visit the link to obtain a list of the geneticists in your country, some of whom may be researchers that do not provide medical care.
Parent Resources
- The Parent Technical Assistance Center Network provides a list of the Parent Training and Information Centers in each state. These centers are funded by the United States Department of Education to provide early intervention and special education information and training to parents of children with disabilities from birth to age 26. Click on the link to find the Parent Center in your state.


Scientific Conferences (Found 3 resources) Resources where you can find information on completed and upcoming scientific conferences and programs. Disclaimer Past Conferences RDCRN 3rd Conference on Clinical Research for Rare Diseases, October 2, 2012 Location: Hilton Washington DC/Rockville Hotel & Executive Meeting Center, Rockville, MD Description: Clinical research in rare diseases presents a number of challenges and unique issues that are not usually considered in the training of clinical investigators through existing training programs. Goals of the conference include: direct instruction of trainees and new investigators in rare disease research methodology; development of a reusable curriculum/syllabus on rare disease research methodology; and stimulation of ideas regarding the unique issues facing investigators engaged in the study of rare diseases. 2010 Genetic Alliance Annual Conference , July 15, 2010 - July 18, 2010 Location: Bethesda North Marriott Hotel and Conference Center, Bethesda, Maryland Description: The Genetic Alliance Annual Conference is consistently inspirational and enables partnership among all stakeholders: advocates and community leaders, health and industry professionals, policymakers and academicians. VI International Conference on Rare Diseases and Orphan Drugs (ICORD 2010): Global Approach to Accessibility in Rare Diseases, Orphan Drugs and Neglected Diseases , March 18, 2010 - March 20, 2010 Location: Palais Rouge Convention Center, Palermo, Buenos Aires Description: For the first time, the VI International Conference on Rare Diseases and Orphan Drugs (ICORD 2010) was convened in the southern hemisphere in agreement with its aim of globalization of rare diseases research and orphan products development activities.

Scientific Conferences (Found 3 resources)
Resources where you can find information on completed and upcoming scientific conferences and programs. Disclaimer

Past Conferences
- RDCRN 3rd Conference on Clinical Research for Rare Diseases, October 2, 2012
  Location: Hilton Washington DC/Rockville Hotel & Executive Meeting Center, Rockville, MD
  Description: Clinical research in rare diseases presents a number of challenges and unique issues that are not usually considered in the training of clinical investigators through existing training programs. Goals of the conference include: direct instruction of trainees and new investigators in rare disease research methodology; development of a reusable curriculum/syllabus on rare disease research methodology; and stimulation of ideas regarding the unique issues facing investigators engaged in the study of rare diseases.
- 2010 Genetic Alliance Annual Conference , July 15, 2010 - July 18, 2010
  Location: Bethesda North Marriott Hotel and Conference Center, Bethesda, Maryland
  Description: The Genetic Alliance Annual Conference is consistently inspirational and enables partnership among all stakeholders: advocates and community leaders, health and industry professionals, policymakers and academicians.
- VI International Conference on Rare Diseases and Orphan Drugs (ICORD 2010): Global Approach to Accessibility in Rare Diseases, Orphan Drugs and Neglected Diseases , March 18, 2010 - March 20, 2010
  Location: Palais Rouge Convention Center, Palermo, Buenos Aires
  Description: For the first time, the VI International Conference on Rare Diseases and Orphan Drugs (ICORD 2010) was convened in the southern hemisphere in agreement with its aim of globalization of rare diseases research and orphan products development activities.


Clinical Trials & Research (Found 2 resources) Resources where you may find research studies and clinical trials. Disclaimer NIH Clinical Trials and You is a website developed by the National Institutes of Health (NIH) to help people learn more about clinical trials, why they matter, and how to participate. Patient Registry ResearchMatch is a free national research registry designed to bring together patients, healthy volunteers and researchers. Anyone from the United States can register with ResearchMatch, and a parent, legal guardian, or caretaker may register on behalf of a volunteer. Researchers from participating institutions use the ResearchMatch database to search for patients or healthy volunteers who meet the study criteria. Many studies are looking for healthy people of all ages, while some are looking for people with specific illnesses. ResearchMatch was developed by major academic institutions across the country and is funded by the National Center for Advancing Translational Sciences.

Clinical Trials & Research (Found 2 resources)
Resources where you may find research studies and clinical trials. Disclaimer

- NIH Clinical Trials and You is a website developed by the National Institutes of Health (NIH) to help people learn more about clinical trials, why they matter, and how to participate.
Patient Registry
- ResearchMatch is a free national research registry designed to bring together patients, healthy volunteers and researchers. Anyone from the United States can register with ResearchMatch, and a parent, legal guardian, or caretaker may register on behalf of a volunteer. Researchers from participating institutions use the ResearchMatch database to search for patients or healthy volunteers who meet the study criteria. Many studies are looking for healthy people of all ages, while some are looking for people with specific illnesses. ResearchMatch was developed by major academic institutions across the country and is funded by the National Center for Advancing Translational Sciences.