Does it have anything to do with the age of the parents?
2006-11-16 20:44:35 · 10 answers · asked by rabble rouser 6 in Pregnancy & Parenting ➔ Pregnancy
What causes Down’s syndrome?
As yet, we do not know what causes the presence of extra number 21 chromosome. It can come from either the mother or the father. The most common type of Down’s syndrome, Standard Trisomy 21 (also known as Primary Trisomy 21 or Regular Trisomy 21), occurs because of an unusual cell division which has produced either an egg or a sperm with 24 chromosomes instead of 23. When this egg or sperm fuses with an ordinary egg or sperm, the first cell of the developing baby has 47 chromosomes instead of 46, and all that baby’s cells will have 47 chromosomes. There is no way of predicting whether a person is more or less likely to make eggs or sperm with 24 chromosomes. We know that babies born to older mothers have a higher chance of having Down’s syndrome, but we do not know why.
2006-11-16 20:54:44 · answer #1 · answered by Laurie V 4 · 1⤊ 0⤋
Humans have 23 pairs of chromosomes in each cell. A chromosome basically contains the DNA of a human. Simply stated, Downs Syndrome means that a person has an extra chromosome, specifically chromosome number 21. I.e., instead of each cell containing two copies of chromosome 21, there are three copies. Simply stated, this genetic abnormality opens the door for an array of different problems that you can probably research on your own.
Yes, maternal age definitively influences the incidence of Downs Syndrome. Usually, age 40 is considered the "threshold" age after which the rate of incidence grows rapidly. At age 40, there is approximately a 1% likelihood of giving birth to a Downs Syndrome child. That probability increases to 10% by age 49. While Downs Syndrome can occur to a mother of any age, the likelihood is very small for young mothers.
There is no link to the age of the father to Downs Syndrome.
2006-11-17 04:59:39 · answer #2 · answered by sothere! 3 · 1⤊ 1⤋
Down Syndrome is caused by the presence of an extra 21st chromosome. Nothing to do with the parents' ages.
2006-11-17 04:52:22 · answer #3 · answered by God 4 · 0⤊ 1⤋
Down syndrome or trisomy 21 (British Down's syndrome) is a genetic condition resulting from the presence of all or part of an extra 21st chromosome.
2006-11-17 04:56:48 · answer #4 · answered by Gaelan M 2 · 0⤊ 0⤋
Too much genetic code.... a failure of an allele to split on the 21st chromosome, which is why its called "trisomy 21".
Pregnancys of women over 35 start to see a signigicant increase in probabilty for developement.
2006-11-17 04:58:09 · answer #5 · answered by Stonerscientist 2 · 0⤊ 0⤋
Look at this website and it will tell you eveything you need to know. There is increased risk with age but not too much. Have a look and put your mind at ease.
http://www.mayoclinic.com/health/down-syndrome/DS00182
2006-11-17 04:56:39 · answer #6 · answered by rcarterblignaut 1 · 0⤊ 0⤋
An extra chromosome; the 33rd chromosome. We just did it in psychology.
Yes, when the woman becomes older then it quadruples in likelyhood.
Just love what ever comes along and all will be fine with the world.
2006-11-17 04:51:48 · answer #7 · answered by Put_ya_mitts_up 4 · 2⤊ 0⤋
The fetus carries an extra chromosome.
Age of the parents may be a factor.
2006-11-17 04:51:21 · answer #8 · answered by Susan M 7 · 1⤊ 0⤋
it's not inherited...it's caused by a chromosomal abberation. but, risk increases after age 35 (of the mother--not father)
2006-11-17 04:52:52 · answer #9 · answered by christina rose 4 · 1⤊ 0⤋
nope it's just a genetic mutation
2006-11-17 04:51:55 · answer #10 · answered by BLEHH 3 · 0⤊ 2⤋