What is Down Syndrome?

Down syndrome is a chromosomal disorder caused when an error in cell division results in an extra 21st chromosome.

In every cell in the human body there is a nucleus, where genetic material is stored in genes. Genes carry the codes responsible for all of our inherited traits and are grouped along rod-like structures called chromosomes. Typically, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent.

This additional genetic material alters the course of development and causes the characteristics associated with 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.

Symptoms:

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.

Children and adults with Down syndrome have distinct facial features. Though not all people with Down syndrome have the same features, some of the more common features include:

• Flattened face
• Small head
• Short neck
• Protruding tongue
• Upward slanting eye lids (palpebral fissures)
• Unusually shaped or small ears
• Poor muscle tone
• Broad, 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 called Brushfield's spots
• Short height

Infants with Down syndrome may be average size, but typically they grow slowly and remain shorter than other children the same age.

Types of Down syndrome:

There are three types of Down syndrome:

Trisomy 21

Trisomy 21 means there’s an extra copy of chromosome 21 in every cell. This is the most common form of Down syndrome.

Mosaicism

Mosaicism occurs when a child is born with an extra chromosome in some but not all of their cells. People with mosaic Down syndrome tend to have fewer symptoms than those with trisomy 21.

Translocation

In this type of Down syndrome, children have only an extra part of chromosome 21. There are 46 total chromosomes. However, one of them has an extra piece of chromosome 21 attached.

Diagnosis

Women with a higher chance of having a child with Down syndrome may receive screening and diagnostic tests.

Screening tests can estimate the probability of Down syndrome being present. Some diagnostic tests can definitively tell whether the fetus has the condition.

Treatment

There is no specific treatment for Down syndrome.

People with the syndrome will receive care for health problems, just as other people do. However, additional health screening for common problems may be recommended.

Early intervention can help the individual maximize their potential and prepare them to take an active role in the community.

Apart from physicians, special educators, speech therapists, occupational therapists, physical therapists, and social workers can all help. The National Institute for Child Health and Human Development (NICHHD) urge all participants to provide stimulation and encouragement.

Children who have specific difficulties with learning and development may be eligible for educational support, either in a mainstream or specialized school. In recent years, the tendency has increasingly been to attend mainstream schools, often with additional support to help them integrate and progress.

Some children will have an Individualized Education Plan (IEP), supported by various specialists.