Down Syndrome

There is no actual chromosomal change, there is an extra chromosome.

A person with Down Syndrome will have 3 chromosomes for the 21st autosome. Karyotypes show these chromosomes which help to diagnose Down Syndrome.

Greater than 90 percent of patients with Down syndrome have trisomy 21. A patient with trisomy 21 has three copies of chromosome 21.

Down syndrome is classified as a genetic disorder and it includes a combination of characteristic facial features, often some degree of mental retardation, and sometimes heart defects. Many people with Down syndrome also have hearing and vision problems.

Down syndrome is one of the most common genetic birth defects.

It affects between 1 in 800 and 1 in 1000 babies.

Down syndrome is classified as a genetic disease since it is an abnormality in an individual's genome.

These abnormalities can range from very small to major ones -- from a single mutation in a single base in the DNA of a single gene to a chromosome abnormality that involves the addition or subtraction of an entire chromosome or set of chromosomes. This is the case with Down syndrome where there is an extra copy of chromosome 21.

Usually each human sperm and egg contain 23 chromosomes. When they unite, they create 23 pairs or 46 total. Sometimes things don't work out perfectly when an egg or a sperm cell is forming causing it to have an extra chromosome 21. When this happens Down syndrome results.

No, but consuming alcohol during pregnancy can lead to impaired mental development in a condition called Fetal Alcohol Syndrome.

It is very unlikely that two people with Down Syndrome are able to conceive.

Most males with Down Syndrome are infertile, with only 3 recorded instances of a down syndrome father being able to conceive.

Most females with Down Syndrome have both conception and birthing problems, leading to a high miscarriage rates for those who are able to conceive. Females with down syndrome have much lower fertility rates.

I'm not sure but being around people with down syndrome, it seems like they are over emotional like they can get mad easily and if they don't get what they want they get upset. Like if they are older, they seem more childlike

Yes. Any child can have down syndrome, as long as the parents pass the gene. Luckily, most people don't have it.

No. Older women are more likely to have Down Syndrome babies. The risk is highest after age 35.

they rarely have any limitations

All kids are different i talked at 10months but my son didn't start talking alot until he was almost 2 I think as long as they can do other normal stuff (sitting crawling walking etc.) they are fine some kids just don't talk

People with Down syndrome all have similar facial features and can look like they have Asian ancestry. In the past, people thought that the different races had evolved by different amounts, with the European being the most evolved and the other races were all less intelligent or able.

The faces of the Down syndrome people looked like the Mongols of Asia, who were considered very undeveloped and unintelligent. So people thought they were a throwback and called them Mongoloids, both as a reference to their appearance and their supposedly unevolved intelligence.

No. Gene therapy alters a person's genetic code, generally by inserting a genetic sequence. Trisomy 21 (downs syndrome) is caused by the presence of a copy (or part of a copy) of the 21st chromosome. Genetic therapy would not be able to remove this extra chromosome. It might be possible (in the future) to "turn off" the extra chromosome, and stop trisomy-21 at the embryo stage. However, by the time a person is born, the physical damage from downs syndrome has been done. After a few months to a year or so, the mental damage from downs syndrome will also be done. So no "treatment" for downs syndrome will be possible using genetic modification such as gene therapy.

Because the average human is born with 46 chromosomes, 23 from their mother and 23 from their father. Some one with Down's syndrome is born with a 47th chromosome, that is the "Down's Syndrome".

After having one child with Down Syndrome, the likelihood of having another is about one percent. If the first child's Down Syndrome is due to translocation trisomy 21, the likelihood of another Down Syndrome child increases. As far as researchers know at this point, Down Syndrome is not attributed to the parents' behavior prior and/or during pregnancy or any environmental factors. The incidence of Down Syndrome does rise if the mother is older than 35, but it does not account for a large number of Down Syndrome children. Since more women are having children at ages younger than 35, then number of babies born with the syndrome is higher in younger age groups.

== == * Down syndrome is also known as Trisomy 21. In years gone by, it was also known as Mongolism, although that term is no longer used.

* It has also been called "Up syndrome" by some people, because children with Down syndrome tend to be happy a lot.

No, not necessarily, but Down's Syndrome can lead to other deadly diseases, but it doesn't kill you at birth - just gives you strange defects. But they can drastically reduce lives' expectancy. But people are working together to improve the diseases, so their life expectancies are shooting way up. So will, I hope, the rest of ours.

yes.

A person with Down Syndrome may find they have a short attention span, poor eye sight and a need for a routine.

Also, typically the life span of a person with Down Syndrome is cut short at an average of 49 years.

A genetic disorder caused by the presence of all or part of a third copy of chromosome 21.

Down's syndrome usually isn't deadly as such. However, it brings with it a couple of medical problems, like high blood presure and such, which tends to shorten the life span of afflicted persons.