The diagnostic procedures available for prenatal diagnosis of Down syndrome are chorionic villus sampling CVS and amniocentesis. Amniocentesis is usually performed in the second trimester between 15 and 20 weeks of gestation, CVS in the first trimester between 9 and 14 weeks. Down syndrome is usually identified at birth by the presence of certain physical traits: low muscle tone, a single deep crease across the palm of the hand, a slightly flattened facial profile and an upward slant to the eyes.
Because these features may be present in babies without Down syndrome, a chromosomal analysis called a karyotype is done to confirm the diagnosis.
They photograph the chromosomes and then group them by size, number, and shape. By examining the karyotype, doctors can diagnose Down syndrome. Another genetic test called FISH can apply similar principles and confirm a diagnosis in a shorter amount of time. Individuals with Down syndrome are becoming increasingly integrated into society and community organizations, such as school, health care systems, work forces, and social and recreational activities.
Individuals with Down syndrome possess varying degrees of cognitive delays, from very mild to severe. Most people with Down syndrome have cognitive delays that are mild to moderate. Due to advances in medical technology, individuals with Down syndrome are living longer than ever before. In , children with Down syndrome were expected to survive to age nine.
With the discovery of antibiotics, the average survival age increased to 19 or More and more Americans are interacting with individuals with Down syndrome, increasing the need for widespread public education and acceptance. These downloadable versions of the Preferred Language Guide are available to print and distribute:. Andrew Harris is an avid runner and climber, enjoys movies, music, animals, and anything outdoors.
Andrew, Max, and Amy believe there are no limits to what Andrew can accomplish and with the opportunity, he can do anything he puts his mind to. Donate to NDSS. What is Down Syndrome?
How Common is Down Syndrome? When Was Down Syndrome Discovered? Support NDSS The National Down Syndrome Society envisions a world in which all people with Down syndrome have the opportunity to enhance their quality of life, realize their life aspirations and become valued members of welcoming communities. What Causes Down Syndrome?
Does Down Syndrome Run in Families? How Is Down Syndrome Diagnosed? AT BIRTH Down syndrome is usually identified at birth by the presence of certain physical traits: low muscle tone, a single deep crease across the palm of the hand, a slightly flattened facial profile and an upward slant to the eyes.
Preferred Language Guide. Use this language when referring to Down syndrome and people who have Down syndrome: People with Down syndrome should always be referred to as people first. Using this word is hurtful and suggests that people with disabilities are not competent.
Down syndrome is named for the English physician John Langdon Down, who characterized the condition, but did not have it. While Down syndrome is listed in many dictionaries with both popular spellings with or without an apostrophe s , the preferred usage in the United States is Down syndrome.
Brighter Tomorrows www. Down syndrome is a chromosomal condition that is associated with intellectual disability, a characteristic facial appearance, and weak muscle tone hypotonia in infancy. All affected individuals experience cognitive delays, but the intellectual disability is usually mild to moderate. People with Down syndrome often have a characteristic facial appearance that includes a flattened appearance to the face, outside corners of the eyes that point upward upslanting palpebral fissures , small ears, a short neck , and a tongue that tends to stick out of the mouth.
Affected individuals may have a variety of birth defects. Many people with Down syndrome have small hands and feet and a single crease across the palms of the hands. About half of all affected children are born with a heart defect.
Digestive abnormalities, such as a blockage of the intestine, are less common. Individuals with Down syndrome have an increased risk of developing several medical conditions. These include gastroesophageal reflux, which is a backflow of acidic stomach contents into the esophagus, and celiac disease , which is an intolerance of a wheat protein called gluten. About 15 percent of people with Down syndrome have an underactive thyroid gland hypothyroidism.
The thyroid gland is a butterfly-shaped organ in the lower neck that produces hormones. Individuals with Down syndrome also have an increased risk of hearing and vision problems. Additionally, a small percentage of children with Down syndrome develop cancer of blood-forming cells leukemia.
Delayed development and behavioral problems are often reported in children with Down syndrome. Affected individuals can have growth problems and their speech and language develop later and more slowly than in children without Down syndrome.
Additionally, speech may be difficult to understand in individuals with Down syndrome. A small percentage of people with Down syndrome are also diagnosed with developmental conditions called autism spectrum disorders, which affect communication and social interaction. People with Down syndrome often experience a gradual decline in thinking ability cognition as they age, usually starting around age Down syndrome is also associated with an increased risk of developing Alzheimer disease , a brain disorder that results in a gradual loss of memory, judgment, and ability to function.
Approximately half of adults with Down syndrome develop Alzheimer disease. Although Alzheimer disease is usually a disorder that occurs in older adults, people with Down syndrome commonly develop this condition earlier, in their fifties or sixties.
Down syndrome occurs in about 1 in newborns. About 5, babies with Down syndrome are born in the United States each year, and approximately , people in this country have the condition.
Although women of any age can have a child with Down syndrome, the chance of having a child with this condition increases as a woman gets older. Most cases of Down syndrome result from trisomy 21 , which means each cell in the body has three copies of chromosome 21 instead of the usual two copies. Less commonly, Down syndrome occurs when part of chromosome 21 becomes attached translocated to another chromosome during the formation of reproductive cells eggs and sperm in a parent or very early in fetal development.
Affected people have two normal copies of chromosome 21 plus extra material from chromosome 21 attached to another chromosome, resulting in three copies of genetic material from chromosome Though not all people with Down syndrome have the same features, some of the more common features include:.
Infants with Down syndrome may be average size, but typically they grow slowly and remain shorter than other children the same age. Most children with Down syndrome have mild to moderate cognitive impairment. Language is delayed, and both short and long-term memory is affected.
Children with Down syndrome usually are diagnosed before or at birth. However, if you have any questions regarding your pregnancy or your child's growth and development, talk with your doctor. Human cells normally contain 23 pairs of chromosomes. One chromosome in each pair comes from your father, the other from your mother. Down syndrome results when abnormal cell division involving chromosome 21 occurs.
These cell division abnormalities result in an extra partial or full chromosome This extra genetic material is responsible for the characteristic features and developmental problems of Down syndrome. Any one of three genetic variations can cause Down syndrome:.
Most of the time, Down syndrome isn't inherited. It's caused by a mistake in cell division during early development of the fetus. Translocation Down syndrome can be passed from parent to child.
However, only about 3 to 4 percent of children with Down syndrome have translocation and only some of them inherited it from one of their parents. When balanced translocations are inherited, the mother or father has some rearranged genetic material from chromosome 21 on another chromosome, but no extra genetic material.
This means he or she has no signs or symptoms of Down syndrome, but can pass an unbalanced translocation on to children, causing Down syndrome in the children. People with Down syndrome can have a variety of complications, some of which become more prominent as they get older. These complications can include:. For people with Down syndrome, getting routine medical care and treating issues when needed can help with maintaining a healthy lifestyle. Life spans have increased dramatically for people with Down syndrome.
Today, someone with Down syndrome can expect to live more than 60 years, depending on the severity of health problems. There's no way to prevent Down syndrome. If you're at high risk of having a child with Down syndrome or you already have one child with Down syndrome, you may want to consult a genetic counselor before becoming pregnant.
A genetic counselor can help you understand your chances of having a child with Down syndrome.
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