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.
However, many individuals can go undiagnosed up into adulthood and there are still thousands who never receive a diagnosis. Mosaic Down syndrome can be found in 1-2% of individuals and is where some of the cells in the body are normal and other cells have trisomy 21.
People with Down syndrome don't 'all look the same'. The condition is characterised by certain physical features, but people can have all of them — or none. A person with Down syndrome typically looks more like their close family members than another person with the condition.
Most adults with Down syndrome are aware they have Down syndrome. Children with Down syndrome live ordinary lives filled with extraordinary needs. You cannot have mild or severe Down syndrome. Either you have it or you do not.
Down syndrome symptoms vary from person to person and can range from mild to severe. No matter how severe the condition is, people with Down syndrome have a widely-recognized appearance.
Kids with Down syndrome often have similar physical features, such as a flat facial profile, an upward slant to the eyes, small ears, and a tongue that tends to stick out. Low muscle tone (called hypotonia) is also common in kids with Down syndrome but is less obvious as they get older.
So, are Down syndrome and autism the same thing or the same disorder? No. They are distinct disorders with different causes that may show some similar symptoms, but also differences.
There are three types of Down syndrome: trisomy 21 (nondisjunction), translocation and mosaicism. Trisomy 21 (nondisjunction) accounts for 95% of known cases of Down syndrome.
Today the average lifespan of a person with Down syndrome is approximately 60 years. As recently as 1983, the average lifespan of a person with Down syndrome was 25 years.
About eight or nine out of 10 cases of Down syndrome are detected (classified as screen positive). This means that one or two out of 10 pregnancies with Down syndrome are missed (classified as screen negative).
Down syndrome, Edward syndrome and Patau syndrome are the most common forms of trisomy.
Children with Down syndrome usually have delayed speech and language development. Typically, these children have a much harder time learning to talk (expressive language) than with understanding what they hear (receptive language).
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. Mosaicism is usually described as a percentage.
Small head, ears, and mouth. Upward slanting eyes, often with a skin fold that comes out from the upper eyelid and covers the inner corner of the eye. White spots on the colored part of the eye (called Brushfield spots) Wide, short hands with short fingers.
Mosaicism. Mosaicism (or mosaic Down syndrome) exists when there are a mixture of two types of cells, some containing the usual 46 chromosomes and some containing 47. Those cells with 47 chromosomes contain an extra chromosome 21. Mosaicism is the least common form of Down syndrome.
Most individuals with Down syndrome have mild (IQ: 50–69) or moderate (IQ: 35–50) intellectual disability with some cases having severe (IQ: 20–35) difficulties. Those with mosaic Down syndrome typically have IQ scores 10–30 points higher than that.
In almost all cases, Down's syndrome does not run in families. Your chance of having a baby with Down's syndrome increases as you get older, but anyone can have a baby with Down's syndrome. Speak to a GP if you want to find out more.
Many people with Down syndrome will make noises or do motor activities (e.g., arm movements) that appear to be self-stimulatory. These are called stereotypies (also known as self-stimulatory behavior). * They can include making sounds or doing repetitive movements or repetitively moving objects.
Behavioral issues can include attention problems, obsessive/compulsive behavior, and stubbornness or tantrums. A small percentage of people with Down syndrome are also diagnosed with developmental conditions called autism spectrum disorders, which affect communication and social interaction.
A recent study suggests that a 20-year-old father doubles the chance of Down syndrome as compared to one who's 40.
Diagnostic tests during pregnancy
Diagnostic tests that can identify Down syndrome include: Chorionic villus sampling (CVS). In CVS, cells are taken from the placenta and used to analyze the fetal chromosomes. This test is typically performed in the first trimester, between 10 and 13 weeks of pregnancy.
Mosaic Down syndrome happens when an extra copy of chromosome 21 is present in some, but not all, of the body's cells. Chromosomes contain all of the genetic information that tells our body how to grow and function.
Babies with Down's syndrome are like any newborn babies.
They'll be eating, sleeping, crying, and needing love and cuddles just like all babies. Some babies with Down's syndrome might need extra help. This could be with things like feeding.