Down Syndrome

Essay by Anonymous UserHigh School, 11th gradeB, January 1996

download word file, 2 pages 3.0

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-Down Syndrome-

-An Informative Essay-

Down Syndrome is the name for babies born with a disorder

related to their chromosomes. It is caused when meiosis occurs

and an error occurs in the cells development. The reason for

this defect is often because the parent is over 40 or for some

other reason their meiosis is not 'Up to par.'

The actual defect is an extra chromosome is developed during

cell development. The abnormal development results in 47

chromosomes rather than the usual 46 (23 from each parent).

This extra gene causes problems in the child's physical and

mental development. There are an estimated 5000 babies with Down

Syndrome born in America every single year. While the chances of

having a Down Syndrome baby are slim, (1 in 1000) it is still an

issue that to-be parents should discuss and prepare for.

People with Down Syndrome are identified by many physical

characteristics. Some of these are: larger or almond shaped eyes

(sometimes Brushfield spots on the irises), smaller than normal

features, such as smaller ears or a smaller nose, short stubby

fingers, a single palmar crease on their hands, and having

exceptional social intelligence.

Because Down Syndrome is cause by a cell abnormality during

meiosis, it can not really be proven that Down Syndrome is

hereditary. A perfectly healthy mother could have a Down

Syndrome baby even though there was never any sign of the

disorder in her pedigree. There are however, three different

kinds of Down Syndrome. 95% of Down Syndrome babies have Trisomy

21. This is the presence of extra genetic material on the 21st

pair of chromosomes. Around 4% have what is called

Translocation. This is where the extra chromosome 21 decided to

break away and attach itself to another chromosome. The last 1%

is made...