Triploidy is the presence of an additional set of chromosomes in the cell for a total of 69 chromosomes rather than the normal 46 chromosomes per cell. The extra set of chromosomes originates either from the father or the mother during fertilization.
What happens if you have an extra set of chromosomes?
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.
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 2 chromosome?
Trisomy 2 mosaicism is a rare chromosome disorder characterized by having an extra copy of chromosome 2 in a proportion, but not all, of a person’s cells . Many cases of trisomy 2 mosaicism result in miscarriage during pregnancy.
What happens if you have 22 chromosomes?
Other changes in the number or structure of chromosome 22 can have a variety of effects. Intellectual disability, delayed development, delayed or absent speech, distinctive facial features, and behavioral problems are common features.
What are 2 characteristics of Down syndrome?
A few of the common physical traits of Down syndrome are low muscle tone, small stature, an upward slant to the eyes, and a single deep crease across the center of the palm – although each person with Down syndrome is a unique individual and may possess these characteristics to different degrees, or not at all.
What gender is Down syndrome most common in?
Down syndrome appears to be more common among boys than girls, the study indicates. The condition is also seen more frequently in Hispanic children at birth, though the number of these children appears to level off with that of white children as they age. Black children appear less likely to have Down syndrome.
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.