What is XYY syndrome?
XYY syndrome is a syndrome that affects males. Under normal circumstances, a male has an X and a Y chromosome but in cases of XYY syndrome the individual has an extra Y chromosome. For some males with this syndrome, signs and symptoms are barely noticeable. For others, signs and symptoms may include learning disabilities, speech delay, low muscle tone (hypotonia), and being taller than expected.
How common is XYY syndrome?
XYY syndrome is a rare chromosomal disorder present at birth that affects only males. It is estimated to occur in approximately one in 1,000 live births. Please discuss with your doctor for further information.
What are the symptoms of XYY syndrome?
The signs and symptoms of XYY syndrome can range from barely noticeable to more severe. It is thought that some males with XYY syndrome may never be diagnosed because the signs and symptoms may not be noticeable. For other males, signs and symptoms such as low muscle tone (hypotonia) and/or speech delay may begin in late infancy or early childhood.
Some boys with XYY syndrome may have difficulty in certain subjects in school such as reading and writing. However, boys with this syndrome do not typically have intellectual disability.
Other signs and symptoms of XYY syndrome may include asthma, dental problems, and acne. Boys with the syndrome don’t typically have physical features different from most people, but they may be taller than expected. These boys are not expected to have differences in the appearance of the sex organs (genitalia).
Some males with XYY syndrome have behavioral differences such as autism spectrum disorder (usually on the milder end) or attention deficit hyperactivity disorder (ADHD). Boys with XYY syndrome are also at an increased risk to have anxiety or mood disorders.
Most boys with XYY syndrome go through normal sexual development, and fertility is expected to be normal. However, some boys with the syndrome may develop testicular failure (when the testes can’t produce sperm or testosterone), which can lead to problems with fertility.
There may be some symptoms not listed above. If you have any concerns about a symptom, please consult your doctor.
When should I see my doctor?
If you or your loved one has any signs or symptoms listed above or you have any questions, please consult with your doctor. Everyone’s body acts differently. It is always best to discuss with your doctor what is best for your situation.
What causes XYY syndrome?
The main cause for the development of XYY syndrome is believed to be an error in cell division in the sperm at the time of conception. The reason as to why these errors occur is still unknown. These errors in cell division results in the child having 47 chromosomes instead of the normal 46 with an extra Y chromosome, which leads to the development of XYY syndrome.
What increases my risk for XYY syndrome?
XYY syndrome is usually not inherited from a parent. Instead, it is typically caused by a random event that happens during the formation of a sperm cell before conception (when the sperm fertilizes the egg). Even though this random event occurs in the sperm cell of the father of a person with XYY syndrome, the syndrome is not inherited from the father because the father himself typically does not have the syndrome. Please consult with your doctor for further information.
Diagnosis & treatment
The information provided is not a substitute for any medical advice. ALWAYS consult with your doctor for more information.
How is XYY syndrome diagnosed?
XYY syndrome may be suspected when a doctor observes signs and symptoms that can be associated with the syndrome such as low muscle tone (hypotonia), speech delay, or learning problems in school. A doctor may then order testing to see if there is a genetic explanation for the signs and symptoms. Tests that may be ordered include:
- Karyotype: a test that is used to view all the chromosomes in a cell
- Chromosomal microarray: a test that looks for extra or missing chromosomes or pieces of chromosomes
In some cases, XYY syndrome may be suspected prenatally based on routine screening tests. A diagnosis can be confirmed with prenatal tests such as an amniocentesis or chorionic villus sampling (CVS).
How is XYY syndrome treated?
The signs and symptoms of XYY syndrome can be managed with a variety of therapies. Occupational therapy may be recommended for infants and young boys who have low muscle tone (hypotonia), and speech therapy may be recommended for boys who have speech delay. Boys with XYY syndrome may be in special education at school, or they may have extra help in some classes.
Other management options for boys with XYY syndrome may include behavioral therapy or medications for boys with attention deficit hyperactivity disorder (ADHD) or behavioral problems. If autism spectrum disorder is present, applied behavioral analysis (ABA) therapy may be recommended. In some cases, hormonal therapy may be used.
Lifestyle changes & home remedies
What are some lifestyle changes or home remedies that can help me manage XYY syndrome?
If you have any questions, please consult with your doctor to better understand the best solution for you.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Review Date: February 8, 2018 | Last Modified: December 8, 2019
47, XYY syndrome https://rarediseases.info.nih.gov/diseases/5674/47-xyy-syndrome Accessed February 7, 2018
XYY Syndrome https://rarediseases.org/rare-diseases/xyy-syndrome/ Accessed February 7, 2018
What is XYY Syndrome: Causes, Symptoms, Treatment https://www.epainassist.com/genetic-disorders/xyy-syndrome Accessed February 7, 2018