49, XXXYY syndrome is a chromosome abnormality that occurs when a male inherits two extra copies of the X chromosome and one extra copy of the Y chromosome. The condition is extremely rare with only a handful of cases reported in the medical literature. Signs and symptoms associated with these cases include severe intellectual disability, distinctive facial features, normal to tall stature, gynecomastia, hypogonadism, and behavioral abnormalities. 49, XXXYY syndrome is likely caused by a mistake (called nondisjunction) that occurs at conception or during the formation of the sperm and/or egg.
Summary
49, XXXYY syndrome is a chromosome abnormality that occurs when a male inherits two extra copies of the X chromosome and one extra copy of the Y chromosome. The condition is extremely rare with only a handful of cases reported in the medical literature. Signs and symptoms associated with these cases include severe intellectual disability, distinctive facial features, normal to tall stature, gynecomastia, hypogonadism, and behavioral abnormalities. 49, XXXYY syndrome is likely caused by a mistake (called nondisjunction) that occurs at conception or during the formation of the sperm and/or egg.49, XXXYY syndrome is a chromosome abnormality that occurs when a male inherits two extra copies of the X chromosome and one extra copy of the Y chromosome. The condition is extremely rare with only a handful of cases reported in the medical literature. Signs and symptoms associated with these cases include severe intellectual disability, distinctive facial features, normal to tall stature, gynecomastia, hypogonadism, and behavioral abnormalities. 49, XXXYY syndrome is likely caused by a mistake (called nondisjunction) that occurs at conception or during the formation of the sperm and/or egg.
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Resource(s) for Medical Professionals and Scientists on This Disease:
Orphanetprovides GARD with information for this disease.
About 49,XXXYY syndrome
Many rare diseases have limited information. Currently GARD aims to provide the following information for this disease:
Population Estimate:Fewer than 1,000 people in the U.S. have thisdisease.
Symptoms:May start to appear as a Newborn.
Cause:This disease is caused by changes in the way information is arranged into chromosomes.
Organizations:Patient organizations are available to help find a specialist, or advocacy and support for this specific disease.
Categories:Birth DefectsGenetic Diseases
When Do Symptoms of 49,XXXYY syndrome Begin?
Symptoms of this disease may start to appear as a Newborn.
The age symptoms may begin to appear differs between diseases. Symptoms may begin in a single age range, or during several age ranges. The symptoms from some diseases may begin at any age. Knowing when symptoms began to appear can help medical providers find the correct diagnosis.
Prenatal
Before Birth
Newborn Selected
Birth-4 weeks
Infant
1-23 months
Child
2-11 years
Adolescent
12-18 years
Adult
19-65 years
Older Adult
65+ years
Symptoms may start to appear as a Newborn.
Symptoms
The types of symptoms experienced, and their intensity, may vary among people with this disease. Your experience may be different from others, and you should consult your primary care provider (PCP) for more information.
This list does not include all possible symptoms related to this disease, but they may include:
Nervous System Nervous System
34 Symptoms
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Body Systems
Symptoms related to this disease may affect different systems of the body. Use the 'Filter and Sort' function to learn more about which body system(s) are affected by this disease and their associated symptom(s).
Medical Term
Abnormal cerebral white matter morphology
Frequency
Uncommon
Very frequent
Very frequent
Always
Description
An abnormality of the cerebral white matter.
An abnormality of the cerebral white matter.
Synonym
Abnormality of subcortical white matter; Abnormality of the cerebral white matter; Cerebral white matter abnormalities; Leukoaraiosis; White matter abnormalities; White matter alterations
Abnormality of subcortical white matter; Abnormality of the cerebral white matter; Cerebral white matter abnormalities; Leukoaraiosis; White matter abnormalities; White matter alterations
34 Symptoms
Causes
Chromosome Disorder
49,XXXYY syndrome is a chromosome disorder, which means it is caused by changes in the way information is arranged into chromosomes.
What Is a Chromosome?
Chromosomes are thread-like structures found inside the nucleus of human cells. Each chromosome is made of DNA, and DNA is passed from parents to their children.
Humans usually have 46 chromosomes. The first 22 pairs of chromosomes, called autosomes, are found in males and females. The 23rd pair comprises the sex chromosomes. Each parent passes on 22 autosomes and one sex chromosome to their offspring.
The cells in our bodies must constantly divide and produce new cells. Chromosomes play a key role in making sure DNA is copied and passed along during cell division. However, on rare occasions, mistakes do occur. These mistakes can lead to chromosome disorders.
Patient organizations can help patients and families connect. They build public awareness of the disease and are a driving force behind research to improve patients' lives. They may offer online and in-person resources to help people live well with their disease. Many collaborate with medical experts and researchers.
Services of patient organizations differ, but may include:
Ways to connect to others and share personal stories
Easy-to-read information
Up-to-date treatment and research information
Patient registries
Lists of specialists or specialty centers
Financial aid and travel resources
Please note: GARD provides organizations for informational purposes only and not as an endorsement of their services. Please contact an organization directly if you have questions about the information or resources it provides.
Clinical studies are part of clinical research and at the heart of all medical advances, including rare diseases. Participating in research helps researchers ultimately uncover better ways to treat, prevent, diagnose, and understand human diseases.
What Are Clinical Studies?
Clinical studies are medical research involving people as participants. There are two main types of clinical studies:
Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
Observational studies involve recording changes over time among a specific group of people in their natural settings.
People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.
To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.
Join the All of Us Research Program!
The All of Us Research Program is inviting 1 million people from all backgrounds across the U.S. to help build one of the most diverse health databases in history. Researchers will use the data to learn how our biology, lifestyle, and environment affect health. This may one day help them find ways to treat and prevent diseases.
What if There Are No Available Clinical Studies?
ResearchMatch helps connect people interested in research studies with researchers from top medical centers across the United States. Anyone from the U.S. can register with this free program funded by NIH. Researchers from participating institutions use the database to search for and invite patients or healthy volunteers who meet their study criteria to participate.
What Are Clinical Studies?
Clinical studies are medical research involving people as participants. There are two main types of clinical studies:
Clinical trials determine if a new test or treatment for a disease is effective and safe by comparing groups receiving different tests/treatments.
Observational studies involve recording changes over time among a specific group of people in their natural settings.
People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.
To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.People participate in clinical trials for many reasons. People with a disease may participate to receive the newest possible treatment and additional care from clinical study staff as well as to help others living with the same or similar disease. Healthy volunteers may participate to help others and to contribute to moving science forward.
To find the right clinical study we recommend you consult your doctors, other trusted medical professionals, and patient organizations. Additionally, you can use ClinicalTrials.gov to search for clinical studies by disease, terms, or location.
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Join the All of Us Research Program!
The All of Us Research Program is inviting 1 million people from all backgrounds across the U.S. to help build one of the most diverse health databases in history. Researchers will use the data to learn how our biology, lifestyle, and environment affect health. This may one day help them find ways to treat and prevent diseases.
What if There Are No Available Clinical Studies?
ResearchMatch helps connect people interested in research studies with researchers from top medical centers across the United States. Anyone from the U.S. can register with this free program funded by NIH. Researchers from participating institutions use the database to search for and invite patients or healthy volunteers who meet their study criteria to participate.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Please contact GARD if you need help finding additional information or resources on rare diseases, including clinical studies. Note, GARD cannot enroll individuals in clinical studies.
Use the contact form to send your questions to a GARD Information Specialist.
Please allow 2 to 10 business days for us to respond.
ClinicalTrials.gov, an affiliate of NIH, provides current information on clinical research studies in the United States and abroad. Talk to a trusted doctor before choosing to participate in any clinical study. We recommend checking this site often and searching for studies with related terms/synonyms to improve results.
Please contact GARD if you need help finding additional information or resources on rare diseases, including clinical studies. Note, GARD cannot enroll individuals in clinical studies.
Take steps toward getting a diagnosis by working with your doctor, finding the right specialists, and coordinating medical care.
Data collected from Orphanet and Online Mendelian Inheritance in Man (OMIM) are used to interpret and provide information on rare diseases. This includes names, synonyms, genes, symptom frequency, population estimates and more.
Human Phenotype Ontology (HPO) provides standard terminology that was used by Orphanet and OMIM to represent a disease's phenotypic features. HPO provides information on describing these clinical features.
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