When a sperm fertilizes an egg, the union leads to a baby with 46 chromosomes. But if meiosis doesn’t happen normally, a baby may have an extra chromosome (trisomy), or have a missing chromosome (monosomy).
What causes an extra chromosome?
The extra chromosome 18 or 13 can come from either the mother’s egg cell or the father’s sperm cell. In some instances, the extra chromosome 18 or 13 is attached to another chromosome in the egg or sperm. This is called translocation and is the only form of trisomy 18 or 13 that can be inherited.
Does the extra chromosome come from Mom or Dad?
The extra chromosome can come from uneven division of the chromosomes (called non-disjunction) at either the first or the second meiotic division, in either parent. Where does the extra chromosome come from? The extra chromosome comes from either the mother or the father.
How rare is it to have an extra chromosome?
XYY syndrome is a rare chromosomal disorder present at birth that affects only males. It is estimated to occur in approximately one in 1,000 live births.
What happens if you have an extra chromosome?
For example, an extra copy of chromosome 21 causes Down syndrome (trisomy 21). Chromosomal abnormalities can also cause miscarriage, disease, or problems in growth or development. The most common type of chromosomal abnormality is known as aneuploidy, an abnormal chromosome number due to an extra or missing chromosome.
Does folic acid prevent Down syndrome?
April 17, 2003 — Taking folic acid supplements before and during early pregnancy may not only help prevent neural tube defects in babies, but it may also reduce the risk of Down syndrome.
What are the symptoms of abnormal baby in pregnancy?
Top 5 Conditions of Abnormal Pregnancy
- Vaginal bleeding during pregnancy. …
- Abdominal discomfort, cramping or pain. …
- Frequent headaches and blurred vision. …
- Excessive thirst and sweating. …
- No fetal movement or reduced fetal movement at more than 20 weeks gestation.
What are the signs of Down syndrome during pregnancy?
Some common physical signs of Down syndrome include:
- Flat face with an upward slant to the eyes.
- Short neck.
- Abnormally shaped or small ears.
- Protruding tongue.
- Small head.
- Deep crease in the palm of the hand with relatively short fingers.
- White spots in the iris of the eye.
Can 2 Down syndrome parents have a normal child?
Women with Down syndrome are able to have children, but many men with the condition unfortunately are not able to, however it is possible. Women who have Down syndrome are able to have children; they have a 35-50% chance that their baby will have Down syndrome.