Approximately 1 in 27,000 people are diagnosed with mosaic Down syndrome. Approximately 15% of individuals diagnosed with Trisomy 21 Down syndrome are misdiagnosed and actually have mosaic Down syndrome. There are many individuals who are never diagnosed with this condition.
What happens in mosaic Down syndrome?
Mosaic Down syndrome occurs when an extra copy of the 21stchromosome is passed into the genes shortly after conception. How early on this occurs may help determine how many cells are affected, as only some of the body’s cells will carry this extra chromosome.
Can you have a mild case of Down syndrome?
Each person with Down syndrome is an individual — intellectual and developmental problems may be mild, moderate or severe. Some people are healthy while others have significant health problems such as serious heart defects.
What is a mosaic baby?
When a baby is born with Down syndrome, the healthcare provider takes a blood sample to do a chromosome study. Mosaicism or mosaic Down syndrome is diagnosed when there is a mixture of two types of cells. Some have the usual 46 chromosomes and some have 47. Those cells with 47 chromosomes have an extra chromosome 21.
Can you have downs and not look like it?
Some of the children with Mosaic Down syndrome that we know do not actually look as if they have Down syndrome – the usual physical features are not obvious. This raises some important and difficult social issues and identity issues for both parents and children, which parents have discussed with us.
What age does Down syndrome occur?
It is determined by many factors, but research suggests that there is a higher chance if the mother is older than 35 years of age. Before the age of 30, Down syndrome occurs in fewer than 1 in 1,000 pregnancies. After the age of 40, this figure rises to about 12 in 1,000.
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.