What is Down Syndrome?
Introduction
Down Syndrome (DS) is a genetic disorder that causes a number of academic challenges, behaviour issues, and unique physical characteristics.
Genes come in groups called chromosomes, and children are born with two copies of each chromosome. There are 23 pairs of chromosomes. However, children with DS are born with an extra copy of one of their chromosome – the copy can either be the entire chromosome, or just a part of it. Because this happens with the 21st chromosome, DS is sometimes referred to as “Trisomy-21.”
This copy of the chromosome can results in a number of physical issues, and challenges in the way the child thinks and behaves.
Challenges and strengths
Physical challenges in DS can include:
- Heart problems
- Gastrointestinal problems
- Leukemia
- Hearing loss
- Vision problems
- Thyroid problems
- Difficulty learning motor skills
DS can also affect the way a child thinks and behaves, including:
- Academic difficulties
- Language difficulties
- Memory problems
- Attention-Deficit Hyperactivity Disorder
- Oppositional-Defiant Disorder
- Autism
- Depression
- Obsessive-Compulsive Disorder
For more information about these challenges and the way that they affect children with DS, please see the chapter “Down Syndrome” by Peters and Madduri, in “Children with Complex Medical Issues in Schools: Neuropsychological Descriptions and Interventions”
Important strengths in children with DS can include:
- Willingness to socialize
- Receptive to speech and language therapy
- Receptive to occupational therapy
Diagnosis
DS can be diagnosed prenatally, meaning a doctor can determine whether or not a child has DS before the child is born. And early diagnosis can be made using one of two methods:
- A blood test around the 16th week of pregnancy.
- A two-step test between the 11th and 14th week of pregnancy. This involves an ultrasound and a blood test.
Further tests to confirm this diagnosis can be made during the pregnancy. For more information on these tests, please see the Mayo Clinic’s website at [LINK]
The diagnosis can also be made after the child is born, as Down Syndrome causes recognizable physical characteristics. If it is suspected that the child has DS, a doctor will likely test the child’s DNA.
Causes
DS is caused by an extra copy of part, or all, of the 21st chromosome. There are a number of factors that can increase a child having DS, including:
- the parents already have a child with DS
- the mother or father has a genetic problem with the 21st chromosome
- increased age of the mother