- Illustration shows the chromosomes of a person with Down syndrome
The Genetic Basis of Down Syndrome Open Contextual Dialogue
Down syndrome is a genetic disease that is caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This additional genetic material causes the developmental changes and physical characteristics of Down syndrome.
- The severity of Down syndrome varies between individuals, resulting in lifelong intellectual disability and developmental delays. It is the most common genetic chromosomal disease and the cause of learning difficulties in children. It also commonly causes other medical abnormalities, including heart and gastrointestinal problems.
- A better understanding of Down syndrome and early intervention can greatly improve the quality of life of children and adults with this disorder and help them live full lives. Down syndrome Treatment in Khammam
\Everyone with Down syndrome is an individual – intellectual and developmental problems can be mild, moderate, or severe. Some people are healthy while others have significant health problems such as serious heart defects.
Children and adults with Down syndrome have different facial features. While not all people with Down syndrome have the same characteristics, some of the most common characteristics include:
- Flattened face
- Small head
- Short neck
- Protruding tongue
- Eyelids tilted upwards (eyelid tears)
- Unusually shaped or small ears
- Poor muscle tone
- Wide and short hands with a single crease in the palm
- Relatively short fingers and small hands and feet
- Excessive flexibility
- Tiny white spots on the colored part (iris) of the eye are called brushfield spots
- Low altitude
Human cells normally contain 23 pairs of chromosomes. One chromosome in each pair comes from your father and the other from your mother.
Down syndrome occurs when abnormal cell division occurs on chromosome 21. These abnormalities in cell division result in an additional partial or complete chromosome 21. This additional genetic material is responsible for the characteristics and developmental problems of Down syndrome. Any of the three genetic variations can cause Down syndrome:
Trisomy 21. About 95 percent of Down’s syndrome is caused by trisomy 21 – the person has three copies of chromosome 21 in all cells instead of the usual two. This is caused by abnormal cell division during the development of the sperm or egg.
Mosaic Down Syndrome. In this rare form of Down syndrome, a person has few cells with an extra copy of chromosome 21. This mosaic of normal and abnormal cells is caused by abnormal cell division after fertilization.
Translocation Down Syndrome. Down syndrome can also occur when part of chromosome 21 is bound (transferred) to another chromosome before or during conception. These children have the usual two copies of chromosome 21, but they also have additional genetic material from chromosome 21 that is tied to a different chromosome. Down syndrome Treatment in Khammam
Some parents are at higher risk of having a baby with Down syndrome. Risk factors are:
Premature age of the mother. A woman’s chances of having a child with Down syndrome increase with age, as older eggs have a higher risk of incorrect chromosome division. A woman’s risk of fathering a child with Down syndrome increases after she is 35 years old. However, most children with Down syndrome are born to women under the age of 35 because younger women have many more babies.
Be a carrier of Down syndrome genetic translocation. Both men and women can pass the genetic translocation of Down syndrome on to their children.
Having a child with Down syndrome. Parents who have a child with Down syndrome and parents who have a translocation themselves are at increased risk of having another child with Down syndrome. A genetic counselor can help parents assess the risk of having a second child with Down syndrome.
There is no way to prevent Down syndrome. If you are at high risk of having a child with Down syndrome, or if you already have a child with Down syndrome, you should see a genetic counselor before you become pregnant. Down syndrome Treatment in Khammam