How does klinefelter syndrome affect a person

The XXY condition that causes Klinefelter syndrome can't be changed, but medical treatment and working with therapists can help a boy's development and lessen the condition's effects.

Even without treatment, most boys with Klinefelter syndrome grow up to live productive, healthy lives. Boys who have Klinefelter syndrome are born with it. It's also called XXY because they have an extra X chromosome in most or all their cells. Usually, a person has 46 chromosomes in each cell, divided into 23 pairs, which includes two sex chromosomes. Half the chromosomes are inherited from the father and the other half from the mother.

The chromosomes contain genes, which determine an individual's characteristics, such as eye color and height. Klinefelter syndrome is not caused by anything the parents did or did not do. The disorder is a random error in cell division that happens when a parent's reproductive cells are being formed. If one of these defective cells contributes to a successful pregnancy, the baby will have the XXY condition in some or all his cells.

When a boy is born with the XXY condition in only some cells, it's called mosaic Klinefelter syndrome. Often, boys and men with this condition have milder signs and symptoms than others with the XXY condition.

Not all boys with Klinefelter syndrome will have noticeable symptoms. Other boys can have symptoms that are physically apparent or problems with speech, learning, and development.

Babies with Klinefelter syndrome typically have weak muscles, reduced strength, and quiet personalities. They also can take longer to do things like sit up, crawl, walk, and speak. Compared with other kids their age, boys with Klinefelter syndrome might have some or all of these symptoms:.

Klinefelter syndrome typically causes a boy's testicles to grow at a slower rate than those of other boys. Despite physical differences and other problems, with the right medical care, early intervention, and ongoing support, guys with Klinefelter syndrome can lead a normal, healthy, and productive life. Reviewed by: Judith L. Ross, MD.

Larger text size Large text size Regular text size. What Is Klinefelter Syndrome? What Causes Klinefelter Syndrome? Boys with Klinefelter syndrome might have some or all of these physical signs: a taller, less muscular body than other boys their age broader hips and longer legs and arms larger breasts gynecomastia weaker bones a lower energy level smaller penis and testicles delayed puberty or only going through puberty partway or, in rare cases, not at all less facial and body hair following puberty Boys with Klinefelter syndrome may have difficulty with spelling, reading, writing, and paying attention.

What Problems Can Happen? How Is Klinefelter Syndrome Diagnosed? How Is Klinefelter Syndrome Treated? Testosterone replacement therapy TRT works by increasing a guy's testosterone levels into the normal range. This can help someone with Klinefelter syndrome develop bigger muscles, a deeper voice, growth of the penis, and facial and body hair.

It also can help improve bone density and reduce any breast growth. However, testosterone therapy cannot increase testicle size or prevent or reverse infertility. Physical therapy, occupational therapy, and speech therapy can build muscle strength and coordination as well as help guys improve their speaking, reading, and writing skills. What Else Should I Know? Ferri FF. In: Ferri's Clinical Advisor Elsevier; Hererra Lizarazo A, et al. Endocrine aspects of Klinefelter syndrome.

Current Opinion in Endocrinology, Diabetes and Obesity. Wick MJ expert opinion. Mayo Clinic. Deng C, et al. Clinical application of noninvasive prenatal screening for sex chromosome aneuploidies in 50, pregnancies: Initial experience in a Chinese hospital. Scientific Reports. Mayo Clinic Laboratories. Cell-free DNA prenatal screen, blood. Accessed Sept. Then click "Submit Query". Organizations Organizations. Organizations Supporting this Disease. InterConnect E-mail: info interconnect.

Living with XXY W. Point Loma Blvd. Do you know of an organization? Living With Living With. Their Web site offers general and condition-specific education resources to help teachers and parents better understand the needs of students who have genetic conditions.

Learn More Learn More. Click on the link to view information on this topic. MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic. MedlinePlus Genetics contains information on Klinefelter syndrome.

This website is maintained by the National Library of Medicine. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them. In-Depth Information Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.

The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health.

Visit the website to explore the biology of this condition. Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge. PubMed is a searchable database of medical literature and lists journal articles that discuss Klinefelter syndrome. Click on the link to view a sample search on this topic. Have a question? References References. Klinefelter syndrome. Genetics Home Reference. Kirmse B.

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