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Causes/Risk Factors

Down syndrome is caused by an extra number 21 chromosome. The three different ways that a person can end up with an extra chromosome 21 which will be discussed here, as well as the link between Down Syndrome and maternal age.

My Screening Test Was Positive, Does It Mean My Baby Has Down Syndrome?
Pregnant women are offered a number of different screening tests during pregnancy, often without adequate explanation. This FAQ will briefly explain screening test results in relationship to the diagnosis of Down syndrome.

Ultrasound Findings that Might Indicate Down Syndrome - Choroid Pexus Cysts
If you have just been told that your baby has a choroid plexus cysts on ultrasound, you are probably frightened and confused, but there is no need to be. Choroid plexus cysts are a common ultrasound finding and always go away over time. The bigger issue with choroid plexus cysts is that they can be a marker that your baby has a small chance to have a serious chromosome problem such as Down syndrome. Read here to learn more about this common ultrasound finding.

First Trimester Prenatal Serum Screening Tests for Down Syndrome
There are several prenatal serum (blood) screening tests now available to screen a pregnancy for Down syndrome. This article discusses first trimester serum screening and what it can and can't tell you.

Did I Cause My Child to Have Down syndrome?
A simple explanation of what causes Down syndrome.

What Is Mosaic Down Syndrome?
Mosaic Down syndrome accounts for 2 to 4% of all cases of Down syndrome. But what exactly is mosaic Down syndrome, and what does it mean for a child who receives this diagnosis?

What Causes Down Syndrome?
Down syndrome is caused by having an extra chromosome number 21. But what exactly does this mean? Read this section to learn more about what is known about the cause of Down syndrome, the types of Down syndrome and the relationship between a mother's age and Down syndrome.

Other Trisomies In Humans
While Down syndrome is the most common human trisomy, other trisomies also can occur. Read here to get some information about the other trisomies seen in humans.

A Video Covering the Basics of Cells, Genes and Chromosomes
A short video discussing the basics of DNA and chromosomes from the University of Utah’s Genetic Science Learning Center. Be sure to click on the “What is Chromosome?” button and turn up the volume so that you can hear the explanations.

What is a Chromosome?
A short video discussing what causes Down Syndrome from About.com

Chromosomes, Trisomies, Translocation and Karyotypes
A multimedia presentation from the University of Washington discussing some of the basics of cytogenetics (the study of chromosomes).

My Child with Down Syndrome Had Leukemia. Signs to Watch For!
I feel proud of him for beating cancer and for many times for reminding us with his smile how important it is to believe and to never give up.

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