5 doctors weighed in:
What is trisomy?
5 doctors weighed in

Dr. James Ferguson
Pediatrics
2 doctors agree
In brief: Error in formation
Humans have 23 pairs of chromosomes or 46 total.
During the formation of the egg, each pair splits and one of each travels to the egg. At conception, the sperm brings one of each & the new embryo now has 23 pairs (two of each). Any time one of the chromosome pairs doesn't split & gives a pair to the egg, a third will come from the sperm and a trisomy of that chromosome is formed.

In brief: Error in formation
Humans have 23 pairs of chromosomes or 46 total.
During the formation of the egg, each pair splits and one of each travels to the egg. At conception, the sperm brings one of each & the new embryo now has 23 pairs (two of each). Any time one of the chromosome pairs doesn't split & gives a pair to the egg, a third will come from the sperm and a trisomy of that chromosome is formed.
Dr. James Ferguson
Dr. James Ferguson
Thank
1 doctor agrees
In brief: Extra chromosome
Trisomy is a genetic conditon in which the person has an extra chromosome.
Trisomy 21or having an extra chromosome #21 is what causes downs syndrome.

In brief: Extra chromosome
Trisomy is a genetic conditon in which the person has an extra chromosome.
Trisomy 21or having an extra chromosome #21 is what causes downs syndrome.
Dr. Charles Kattuah
Dr. Charles Kattuah
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