When was xyy discovered

People normally have 46 chromosomes in each cell. Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics.

As a result of the extra Y chromosome, each cell has a total of 47 chromosomes instead of the usual It is unclear why an extra copy of the Y chromosome is associated with tall stature, learning problems, and other features in some boys and men. Some males with 47,XYY syndrome have an extra Y chromosome in only some of their cells. Most cases of 47,XYY syndrome are not inherited. The chromosomal change usually occurs as a random event during the formation of sperm cells. An error in cell division called nondisjunction can result in sperm cells with an extra copy of the Y chromosome.

If one of these atypical reproductive cells contributes to the genetic makeup of a child, the child will have an extra Y chromosome in each of the body's cells.

It occurs as a random event during cell division in early embryonic development. Genetics Home Reference has merged with MedlinePlus.

Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Health Topics. Health Tools. XYY Syndrome. Reviewed: November 10, Medically Reviewed. XYY syndrome is a genetic condition that occurs when a male is born with an extra Y chromosome.

As children get older, physical symptoms of XYY syndrome can include: 1 ,2 Taller height Slightly larger head size Large teeth Widely spaced eyes Flat feet Fifth fingers that curve inward Increased belly fat Scoliosis Weak muscle tone Hand tremors or motor tics Asthma Delayed development of motor skills, such as sitting and walking However, because these characteristics tend to fall within the normal range for males, often those with XYY syndrome do not get diagnosed.

Being male is the biggest risk factor. People normally have 46 chromosomes in each cell. Females normally have two X chromosomes, while males have one X chromosome and one Y chromosome.

However, boys born with XYY syndrome have an extra Y chromosome in each cell of their body. The exact reason why this error occurs is not known.

Medication Options While medication cannot treat XYY syndrome, some medications can be used to treat conditions related to the syndrome. Editorial Sources and Fact-Checking. Finding services early is important and can greatly increase their ability to help boys live a healthier, more productive life.

Options vary greatly depending on how old a boy is at the time of his diagnosis, whether he has noticeable symptoms, and the severity of those symptoms.

Regular doctor visits. At periodic visits, a doctor can monitor a boy's development for delays, social and language disabilities, or health problems and treat these promptly. Educational support services. Educational support can teach boys ways to keep pace in school. Some might be eligible for an individualized educational program IEP or education plan , which are designed to help children with special needs. Early intervention services. It can be very helpful and often more effective for a boy to have speech , occupational , physical , or developmental therapy in the early months of life or as soon as concerns are found.

Speech therapy and physical therapy can improve a boy's speaking, reading, and writing skills and help increase strength and coordination. Occupational therapy and behavioral therapy can help them develop more confidence and interact better with other children.

The whole family can benefit from counseling to better understand XYY syndrome and help a boy who has it to live a productive life. Early inventions should be considered at infancy for physical therapy, at 15 months for speech delay, at 1st grade for reading and learning issues, and at 3rd grade for anxiety or depression. Boys with XYY syndrome can develop speech, learning, or social challenges at a young age. This can make them more likely to have low self-esteem and lead to school or social problems.

If your son has trouble making friends or struggles in school, talk to your doctor or the principal or school counselor. Counseling and therapy can teach your son practical skills to help him make friends and feel more confident in school, and educational services can help him do well in school.

Talk to your doctor if you have any concerns about your son's physical and emotional development. Despite physical differences and other problems, with the right medical care, early intervention, and ongoing support, a boy with XYY syndrome can lead a normal, healthy, and productive life. Reviewed by: Judith L.