Fact Sheet

What is Turner Syndrome?

Turner Syndrome is a rare chromosomal disorder that affects females. The disorder is characterized by partial or complete loss (monosomy) of one of the X chromosomes. Turner Syndrome is highly variable and can differ dramatically from one person to another. Affected females can potentially develop a wide variety of symptoms, affecting many different organ systems. Common symptoms include short stature and premature ovarian failure, which can result in the failure to attain puberty. Most women with Turner Syndrome are infertile. A variety of additional symptoms can occur including abnormalities of the eyes and ears, skeletal malformations, heart anomalies, and kidney abnormalities. Intelligence is usually normal, but affected individuals may experience certain learning disabilities. Turner Syndrome may be diagnosed before birth or shortly after birth or during early childhood. However, in some cases, the disorder may not be diagnosed until well into adulthood, often as an incidental finding. The exact, underlying cause of Turner Syndrome is not known. Furthermore, most cases do not run in families and appear to occur randomly for no apparent reason (sporadically).

There are different types of Turner Syndrome. Classic Turner Syndrome, also known as “XO” or 45, X karyotype, occurs when the female is missing one complete X. A mosaic karyotype refers to a missing or rearranged X chromosome in some but not all cells in the body chromosome or missing only part of the second chromosome. There are different potential health issues associated with the different types of Turner Syndrome.

How is it manifested?

Appearance: Features of Turner Syndrome may include a short neck with a webbed appearance, low hairline at the back of the neck, low-set ears, hands, and feet that are swollen or puffy at birth, and soft nails that turn upward.

Stature: Girls with Turner Syndrome grow more slowly than other children. Without treatment, they tend to have short stature (around 4 feet, 8 inches) as adults.

Puberty: Most girls with Turner Syndrome do not start puberty naturally.

Reproduction: In most girls with Turner Syndrome, the ovaries are missing or do not function properly. Without the estrogen made by their ovaries, girls with Turner Syndrome will not develop breasts. More than 95% of women with Turner Syndrome cannot become pregnant without assistive technology.

Cardiovascular: Turner Syndrome can cause problems with the heart or major blood vessels. In addition, about 20% of girls and 40% of women with Turner Syndrome have high blood pressure.

Kidney: Kidney function is usually normal in Turner Syndrome, but some people with this condition have kidneys that look abnormal.

Osteoporosis: Women with Turner Syndrome often have low levels of the hormone estrogen, which can put them at risk for osteoporosis. Osteoporosis can cause height loss and bone fractures.

Diabetes: People with Turner Syndrome are at higher risk for Type 2 Diabetes.

Thyroid: Many people with Turner Syndrome have thyroid problems. The most common one is hypothyroidism, or an under-active thyroid gland.

Cognitive: People with Turner Syndrome have normal intelligence. Some, however, have problems learning mathematics and can have trouble with visual-spatial coordination (such as determining the relative positions of objects in space).

Who is affected?

Turner Syndrome affects approximately 1 female in 2,000-2,500 live births.

How is it diagnosed or detected?

The diagnosis is made by a blood test which looks at the complete set of chromosomes of the individual. This is called a karyotype. Karyotype analysis shows if one of the X chromosome pair is missing from the full chromosome set, or if there are any structural differences in the X chromosomes.

Before birth, a diagnosis of Turner Syndrome can be made by taking a sample of amniotic fluid or other fetal tissue to look at the fetal karyotype. Ultrasound is also used to screen for patterns often seen in Turner Syndrome, such as fluid buildup around the neck, and kidney or heart abnormalities.

After birth, a diagnosis of Turner Syndrome is confirmed by taking a sample of blood or other tissue to obtain a karyotype. Because there is a range of health, developmental, social, and learning challenges which might affect girls and women with Turner Syndrome to different degrees, it is important to diagnose Turner Syndrome as early as possible.

Additional Resources:

Turner Syndrome Society of Canada – www.turnersyndrome.ca
The Turner Syndrome Society of Canada, a non-profit charitable organization, was founded in 1981 by an individual with Turner Syndrome who wanted to share experiences and information. Our organization shares up-to-date medical information on Turner Syndrome to families, physicians and the public.
Telephone: (613) 321-2267
Toll-free: 1-800-465-6744

Turner Syndrome Foundation – www.turnersyndromefoundation.org
The Foundation’s advocacy efforts identify these gaps and give voice to leaders who can make a difference. The vision to improve the understanding of Turner Syndrome and to render support for women and children living with Turner Syndrome is made possible by advancing communications and inspiring relevant interest in this women’s health issue.
Toll free: 1-800-594-4585

Books and Literature:

Turner Syndrome across the Lifespan
This book is written for girls and women with Turner Syndrome and their families and it covers issues related to medical and psychosocial health.

Topics discussed include genetics, growth, puberty, infertility and advanced reproductive technology, bone health, diabetes, hearing, school and learning issues, among others. Updated health surveillance issues are outlined. The chapters are interspersed with comments and stories written by girls and women with Turner Syndrome. This book serves as a comprehensive guide for those wanting to learn more about Turner Syndrome.

A Canadian publication, this 240-page book, edited by Jill Hamilton (MD, FRCPC), and Irena Hozjan (RN, BScN, MN), is a comprehensive and up to date overview of Turner Syndrome.

This book can be ordered directly through the Turner Syndrome Society of Canada – www.turnersyndrome.ca

Standing Tall with Turner Syndrome Paperback
This compilation of 18 essays – edited by Claudette Beit Aharon is written by women of various ages who have Turner Syndrome, and share their life experiences living with this condition. There is a foreword by Lynne Levitsky MD, chief of pediatric endocrinology, Massachusetts General Hospital and an introduction by the editor. In addition there is medical information on diagnostic tools and treatments, a FAQ about the syndrome and its ramifications, and a glossary.

The content contained in this document is for general information purposes. It is not the intention to diagnose or treat a child.