What causes downs syndrome?

Answer 1

When a child is diagnosed with DS, this means that they were born with an extra chromosome 21. Giving them a total of 47 rather than 46.This extra chromosome delays physical and educational development.

Answer 2

You cannot do anything to cause your child to have Down Syndrome, drinking,smoking etc in pregnancy does not cause this. Down is caused by a genetic oops where there is an extra chromosome. It is present from the time of conception. You cannot catch Down syndrome.

Answer 3

Down Syndrome (aka trisomy 21) is caused when an extra chromosone number 21 is present.

Normally, each cell in your body has two copies of each of the 44 regular chromosomes, one X and another X (in women) or a Y (in men). When sperm and eggs are formed these pairs line up and then are divided into two sets of 23 chromosomes, one of each.

In the most common form of Down Syndrome the pairs of chromosone 21 do not separate making a sperm or egg with two and another with none. If the sperm or egg with two participates in ferilization the result is a cell with 3 chromosome number 21's (2 from one parent and 1 from the other). This type tends to happen more often as women get older. It is not nearly as strongly related to the age of the father.

In a less common form one of the parents has a chromosome 21 that is duplicated and stuck to itself and so twice as large (a Robertsonian translocation). The person with this defect may be an apparently normal carrier but produce children (and grand children) with Down's.

Answer 4

When a child is diagnosed with DS, this means that they were born with an extra chromosome 21. Giving them a total of 47 rather than 46.This extra chromosome delays physical and educational development.

Answer 5

An extra chromosome 21.