Down Syndrome - NICHD - Eunice Kennedy Shriver National …
网页2023年11月22日 · Down syndrome is a set of cognitive and physical symptoms that result from having an extra chromosome 21 or an extra piece of that chromosome. It is the most common chromosomal cause of mild to moderate intellectual disabilities. People with Down syndrome are at risk for several other health conditions.
Who is at risk for Down syndrome? | NICHD - NICHD - Eunice …
网页2023年11月22日 · Down syndrome is the most frequent chromosomal cause of mild to moderate intellectual disability, and it occurs in all ethnic and economic groups. 2. Researchers know some, but not all, of the risk factors for Down syndrome. For example, parents who have a child with Down syndrome or another chromosomal disorder, or who have a chromosomal ...
What causes Down syndrome? | NICHD - NICHD - Eunice Kennedy …
网页2012年6月11日 · Almost all Down syndrome cases result from complete trisomy 21. 1, 2, 3; Mosaic trisomy 21. Not every cell in the body is exactly the same. In a small percentage (less than 5%) of Down syndrome cases, most of the cells in the body have the extra chromosome, but some of them don’t. This is called “mosaicism.”
About Down Syndrome | NICHD - NICHD - Eunice Kennedy Shriver …
网页2023年11月22日 · Generally, children with Down syndrome reach key developmental milestones later than other children. 2 People with the syndrome are also more likely to be born with heart abnormalities, and they are at increased risk for developing hearing and vision problems, Alzheimer’s disease, and other conditions. 1 …
How do health care providers diagnose Down syndrome?
网页2012年6月11日 · If a woman is pregnant with twins or triplets, a blood test will not be as reliable, because the substances from a Down syndrome fetus may be harder to detect. 2, 3. Prenatal Diagnostic Testing for Down Syndrome. If a screening test suggests the likelihood of Down syndrome, a diagnostic test can be performed.
Down Syndrome | NICHD - NICHD - Eunice Kennedy Shriver …
网页2023年11月30日 · Down syndrome is a set of cognitive and physical symptoms that result from having an extra chromosome 21 or an extra piece of that chromosome. It is the most common chromosomal cause of mild to moderate intellectual disabilities. People with Down syndrome also have some distinct physical features, such as a flat-looking face, and they are at risk for a number of other health conditions.
What are the symptoms of Down syndrome? - NICHD
网页The symptoms of Down syndrome vary from person to person, and people with Down syndrome may have different problems at different times of their lives. Physical Symptoms. Common physical signs of Down syndrome include 1, 2: Decreased or poor muscle tone; Short neck, with excess skin at the back of the neck; Flattened facial profile and nose
What conditions or disorders are commonly associated with Down …
网页2012年6月22日 · Infants with Down syndrome have a 62-fold higher rate of pneumonia, especially in the first year after birth, than do infants without Down syndrome, for example. 2 Hypothyroidism. The thyroid is a gland that makes hormones the body uses to regulate things such as temperature and energy.
About Intellectual and Developmental Disabilities (IDDs)
网页2012年8月12日 · These conditions can also cause other issues, such as behavioral disorders, speech or language difficulties, seizures, and trouble with movement. Cerebral palsy, 5 Down syndrome, Fragile X syndrome, and autism spectrum disorders (ASDs) are examples of IDDs related to problems with the nervous system. Sensory system
What are common symptoms of Klinefelter syndrome (KS)?
网页Klinefelter syndrome: Expanding the phenotype and identifying new research directions. Genetics in Medicine, 5(6), 460-468. Plotton, I., Brosse A., & Lejeune, H. (2010). Is it useful to modify the care of Klinefelter's syndrome to improve the chances of paternity? Annales d'endocrinologie (Paris), 71(6), 494-504. French.