Down syndrome (Trisomy 21) is usually caused by a random error in cell division (nondisjunction) during egg or sperm formation, resulting in an extra copy of chromosome 21; it's generally not inherited, but a rare form, translocation Down syndrome, can be passed down from a parent carrying a balanced chromosome rearrangement, meaning a parent can carry the gene for Down syndrome without having the condition themselves.
An extra chromosome causes Down syndrome. Each human cell typically contains 23 pairs of chromosomes, which totals 46. Down syndrome occurs because of changes in the way cells in chromosome 21 divide. Every person with Down syndrome has an extra chromosome 21 in some or all of their cells.
Yes. A woman with Down's syndrome can have children. If her partner does not have Down's syndrome, the theoretical chance of the child having Down's syndrome is 50%. There have been only a few reports of men with Down's syndrome fathering children.
According to the World Health Organization, the highest prevalence of Down syndrome is reported in countries such as Ireland, Israel, and Turkey. In contrast, countries like Japan and South Africa report a lower incidence of Down syndrome.
Either parent can pass the genetic translocation for Down syndrome on to their children. Having had one child with Down syndrome. Both parents who have one child with Down syndrome and parents who have a translocation themselves are at higher risk of having another child with Down syndrome.
Down syndrome is caused by the presence of an extra chromosome number 21 in the cells of the developing baby. In an unscreened population, about one in every 700 babies is born with Down syndrome. Usually, it is not inherited, so a baby can be affected even if there is no history of Down syndrome in the family.
These factors include geographic region, maternal education, marital status, and Hispanic ethnicity. Because the likelihood that an egg will contain an extra copy of chromosome 21 increases significantly as a woman ages, older women are much more likely than younger women to give birth to an infant with Down syndrome.
Of the people with Down syndrome in the United States: 67% are non-Hispanic and White, 13% non-Hispanic and Black, 16% Hispanic, 3% Asian or Pacific Islander, and 1% American Indian or American Native.
Mosby's Medical, Nursing and Allied Health Dictionary gives an average IQ of between 50 and 60 for Down's syndrome individuals although IQ scores of 120 have been found in some individuals with the syndrome.
Furthermore, though there are some indications in the Census data that incidence at birth may be falling, it is likely to remain comparatively higher than elsewhere because of a relatively large family size and high fertility rates in the 35 years and over age-groups and also because amniocentesis and abortion are not ...
Today the average lifespan of a person with Down syndrome is approximately 60 years. As recently as 1983, the average lifespan of a person with Down syndrome was 25 years.
If both parents have achondroplasia there is a 50 percent chance to have a child with achondroplasia, a 25 percent chance that the child will not inherit the gene and be of average height, and a 25 percent chance that the child will inherit one abnormal gene from each parent, which can lead to severe skeletal problems ...
Family Planning
You can always choose adoption for your unborn baby, including “giving up” a baby with Down syndrome for adoption. “Can you give up a baby with Down syndrome to the family of your choice?” You always have the right to choose the family that you feel is best for your child.
The mental age is rarely over 8 years old, although a few cases of normal Intelligence Quotient (IQ) in children with DS have Page 2 Cognitive development and adaptive functions in children with Down syndrome at different developmental stages 85 been reported 4.
Fetal anomalies linked to Down syndrome may include physical defects affecting different organs and systems. Common anomalies noticed in fetuses with Down syndrome might affect the heart (e.g., atrioventricular septal defects), gastrointestinal tract (such as duodenal atresia), and other structural abnormalities.
Down Syndrome Statistics by Country in 2025
Zack Gottsagen: Actor & Oscar Presenter
Zack starred in the critically acclaimed film The Peanut Butter Falcon alongside Shia LaBeouf and Dakota Johnson. In 2020, he also became the first person with Down syndrome to present at the Oscars.
Since the introduction of screening, Down syndrome pregnancies are often aborted (rates varying from 50 to 85% depending on maternal age, gestational age, and maternal race/ethnicity). There is no cure for Down syndrome. Education and proper care have been shown to provide better quality of life.
I.Q. scores for people with Down syndrome vary, with the average cognitive delays being mild to moderate, not severe. In fact, normal intelligence is possible. If a person with Down syndrome has difficulty with hearing, it can be misinterpreted as a problem with understanding.
Down syndrome is the most common genetic cause of intellectual disability, affecting approximately 1 in every 700 children. It is named for John Langdon Down, the British physician who first recognized the traits of Down syndrome in 1866.
Common physical signs of Down syndrome include a flat face, eyes that slant up, a short neck, small hands and feet, poor muscle tone, and loose joints. Common health problems in childhood include hearing loss, sleep apnea, ear infections, eye diseases, and heart defects.
The chance of having a child affected by Down syndrome increases from about 1 in 1,250 for a woman who conceives at age 25, to about 1 in 100 for a woman who conceives at age 40.
Age is the only factor that has been linked to an increased chance of having a baby with Down syndrome resulting from nondisjunction or mosaicism. However, due to higher birth rates in younger women, 51% of children with Down syndrome are born to women under 35 years of age. (De Graaf et al., 2022).