6 doctors weighed in:
How does a person get down syndrome?
6 doctors weighed in

Dr. William Singer
Pediatrics - Neurology
3 doctors agree
In brief: Chromosomal abnormal
Down syndrome is caused be a chromosomal abnormality tha occurs at the time of fertilization.
It is usually associated with the fertilization of an egg carrying2 number 21 chromosomes.

In brief: Chromosomal abnormal
Down syndrome is caused be a chromosomal abnormality tha occurs at the time of fertilization.
It is usually associated with the fertilization of an egg carrying2 number 21 chromosomes.
Dr. William Singer
Dr. William Singer
Thank
Dr. James Ferguson
Pediatrics
1 doctor agrees
In brief: Dividing Chromasomes
We all have 22 pairs of regular chromosomes (chms) plus an xx or xy of the sex chms.
The pairs split during egg or sperm formation so each has 22 chms + an x or y. If the 21 chromosome doesn't split right & brings a pair to the egg(or sperm) the fertilized egg will have an extra 21 so the infant will have 47 total. All subsequent cells have 47, giving rise to a ds kid.

In brief: Dividing Chromasomes
We all have 22 pairs of regular chromosomes (chms) plus an xx or xy of the sex chms.
The pairs split during egg or sperm formation so each has 22 chms + an x or y. If the 21 chromosome doesn't split right & brings a pair to the egg(or sperm) the fertilized egg will have an extra 21 so the infant will have 47 total. All subsequent cells have 47, giving rise to a ds kid.
Dr. James Ferguson
Dr. James Ferguson
Thank
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