Down Syndrome is the most frequently occurring chromosomal abnormality, occurring in approximately one in every 800-1000 live births. It affects individuals of all ages, races and economic status and occurs equally among boys and girls. Individuals with Down Syndrome are human beings with a chromosomal disorder which usually causes delays in physical, intellectual and language development.
        
        Down Syndrome results from extra material (additional genes) along the 21st chromosome altering the course of development and causing the characteristics typically associated with DS. It is typically caused by an error in cell division (non-disjunction), but may also be caused by 2 other forms of chromosomal abnormalities (translocation and mosaicism).

Chromosomal Variations

1) Trisomy 21 occurs in 95% of all Down Syndrome (DS) cases - results from an error in cell division during the development of the egg and the sperm or during fertilization in this case the 21st chromosome has an extra cell - thus, instead of having a total of 46 chromosomes, DS individuals have 47

2) Translocation

• occurs in 4-5% of all DS cases
• in this case individuals have an extra 21st chromosome that has broken and become attached to another chromosome,usually chromosome 14 or the other chromosome 21

3) Mosaic

• occurs in 1-2% of all cases
• affected persons have cells with different chromosome counts (ie. 46 in some cells and 47 in others)
• those with 47 chromosomes have an extra 21st chromosome

Diagnosis and Common Characteristics

       The diagnosis of DS is usually suspected after birth as a result of the baby's appearance. There are many physical characteristics which form the basis for suspecting an infant has DS. A genetic test is done to confirm the diagnosis. While some infants display many of these symptoms, others may only have a few. Some of the most common traits include:

• low muscle tone
• flat facial profile, somewhat flat nasal bridge and small nose
• upward slanted eyes with folds of skin at the inner corners (epicanthal folds)
• hyper flexibility (excessive ability to extend the joints)
• short, broad hands with a single crease across the palm on one or both hands
• fifth finger has one flex point instead of two
  
• broad feet with short toes
• excessive space between the large and second toe
• short, low-set ears
• short neck, small head
• small oral cavity, large tongue

Common Health Issues

       A child with DS is in need of the same kind of medical care as any other child. An example of a "Health Care Guidelines Record Sheet" is included at the end of the handout. There are, however, situations when the child with DS needs special attention. Some of these include:

• dental care - eruption of teeth is usually delayed and often occurs in an unusual order - primary and permanent teeth may be missing - small and misshapen teeth are found as well as severe crowding due to small oral cavity
• hearing deficits (60-80%) - sensorineural or conductive hearing loss (usually caused by recurrent ear infections)
• feeding and nutritional problems - infants with DS may experience difficulty with coordination of sucking and swallowing - later may develop problems with texture progression - obesity is often noted during adolescence and early childhood
  
• Leukemia (but children with this usually respond nicely to treatment), diabetes, thyroid disease (15%), Alzheimer's, congenital heart disease (40-45%)
• eye/vision problems - congenital cataracts (3%), near-sightedness, far-sightedness, cross-eye etc.
• gastro-intestinal abnormalities - celiac disease (7-16%), blockage of oesophagus, small bowel etc.

Stats and Facts

• Down syndrome is not related to race, nationality or socio-economic status - occurs equally between males and females
• occurs in 1 of 1000 (approx.) - about 4000 births each year
• over 350 000 individuals in the USA have Down Syndrome
• the chance of bearing a child with this disorder increases dramatically with advancing maternal age - however women under 35% give birth to 80% of children with DS due to the fact that on average, they bear more children that women over 35 years
  chance of having a second child with DS is 1 in 100
• there are prenatal tests available to detect Down Syndrome:
  • The Fetal Nuchal translucency Test
  • Amniocentesis
• DS can originate from either the mother or father - approximately 5% of the cases have been traced to the father
• there is a wide variation in mental abilities (may vary from mild to severe, with the majority functioning in the mild to moderate range), behaviour and physical development in individuals with DS - each has his/her own unique personality, capabilities and talents.

Janet's Story

        Janet Dill is a 23 year old woman who is striving for her own place in life. She has to work a little harder at it than most because she was born with down syndrome. That is something that occurs in about one in 600 births. People with down syndrome are just as varied as the rest of the population, but they share some common physical traits and experience some degree of learning difficulty.
         Janet started school at 18 months, went to a Montessauri pre-school as the only downs person in the school, and spent her public school career in classes for the learning disabled. Many similar children today would be much more integrated into the regular classroom. She is an accomplished gymnast and competed at an international level in the 1995 Special Olympics World Games. She is also a good skier and has competed nationally in Special Olympics.
         Currently, Jan is attending a post high school program (her equivalent of college) where she is trying to gain enough skills to live and work on her own. She wants a career, a place to live, friends, and a life. That doesn't sound very much like a handicapped ambition. She can read, write, and do arithmetic (faster with a calculator, but who isn't). She is reasonably adept with a computer for word processing and data entry. She has worked at McDonalds and in child and elder care.

Myths and Truths

Myth: Children with DS all look alike and have passive, loving personalities
Truth: while individuals with DS do have some physical features in common they resemble their families in appearance and temperament much more than they do each other

Myth: Children with DS don't live very long
Truth: Approx. 30-40% of individuals with DS are born with heart defects and some have congenital anomalies - many of these defects are now correctable by surgery - the majority of individuals with DS are expected to live an average life span

Myth: Children with DS are severely mentally disabled
Truth: There is a wide variation in mental abilities, behaviour and physical development in individuals with DS

Myth: Children with DS will never grow up to be independent
Truth: Parents and society are coming to understand the aspirations of persons with DS to participate in all aspects of community life; education, recreation, employment, social and family life

Myth: Children with DS are a financial and emotional burden to their families
Truth: Families raising children with DS face increased challenges, but helping their children grow and develop provides the same rewards that all parents experience

Myth: Down syndrome is a rare genetic disorder
Truth: Down syndrome is the most commonly occurring genetic condition. One in every 800 to 1,000 live births is a child with Down syndrome, representing approximately 5,000 births per year in the United States alone. Today, Down syndrome affects more than 350,000 people in the United States.

Myth: Most children with Down syndrome are born to older parents.
Truth: Eighty percent of children born with Down syndrome are born to women younger than 35-years-old. However, the incidence of births of children with Down syndrome increases with the age of the mother.

Myth: People with Down syndrome are severely retarded.
Truth: Most people with Down syndrome have IQs that fall in the mild to moderate range of retardation. Children with Down syndrome are definitely educable and educators and researchers are still discovering the full educational potential of people with Down syndrome.

Myth: Most people with Down syndrome are institutionalized.
Truth: Today people with Down syndrome live at home with their families and are active participants in the educational, vocational, social and recreational activities of the community. They are integrated into the regular education system, and take part in sports, camping, music, art programs and all the other activities of their communities. In addition, they are socializing with people with and without disabilities, and as adults, are obtaining employment and living in group homes and other independent housing arrangements.

Myth: Parents will not find community support in bringing up their child with Down syndrome.
Truth: In almost every community of the United States there are parent support groups and other community organizations directly involved in providing services to families of individuals with Down syndrome.

Myth: Children with Down syndrome must be placed in segregated special education programs.
Truth: Children with Down syndrome have been included in regular academic classrooms in schools across the country. In some instances they are integrated into specific courses, while in other situations students are fully included in the regular classroom for all subjects. The degree of mainstreaming is based on the abilities of the individual; but the trend is for full inclusion in the social and educational life of the community.

Myth: Adults with Down syndrome are unemployable.
Truth: Businesses are seeking young adults with Down syndrome for a variety of positions. They are being employed in small and medium sized offices: by banks, corporations, nursing homes, hotels and restaurants. They work in the music and entertainment industry, in clerical positions and in the computer industry. People with Down syndrome bring to their jobs enthusiasm, reliability and dedication.

Myth: Adults with Down syndrome are unable to form close interpersonal relationships leading to marriage.
Truth: People with Down syndrome date, socialize and form ongoing relationships. Some are beginning to marry. Women with Down syndrome can and do have children, but there is a 50 percent chance that their child will have Down syndrome. Men with Down syndrome are believed to be sterile, with only one documented instance of a male with Down syndrome who has fathered a child.

Myth: Down syndrome can never be cured.
Truth: Research on Down syndrome is making great strides in identifying the genes on chromosome 21 that cause the characteristics of Down syndrome. Scientists now feel strongly that it will be possible to improve, correct or prevent many of the problems associated with Down syndrome in the future.

What's in the Future?
(quoted from http://www.ndss.org/aboutds/aboutds.html)

        "People with Down syndrome are people first. They may have some of the characteristics generally associated with this condition, but they are overwhelmingly unique and must be treated as individuals. Over the past few decades, beginning with Section 504 of The Rehabilitation Act of 1973, continuing with The Education for All Handicapped Children Act of 1975 and culminating with the passage of the Americans with Disabilities Act in 1991, people with Down syndrome have been granted equal protections under federal law.
         Ensuring equal treatment and access to services is a struggle that every family of a child with Down syndrome faces. Daily, these individuals strive to accomplish the same goals as everyone else: self-fulfillment, pride in their achievements, inclusion in the activities of the community and the challenge of reaching their full potential.
         Daily, people with Down syndrome venture out into the community: to schools, jobs and leisure activities. Some live with family, some with friends and some independently. They form ongoing interpersonal relationships and some may marry. Women with Down syndrome are fertile and can have children.
         The opportunities available to people with Down syndrome today have never been greater. However, it is only through the collective efforts of parents, professionals and concerned citizens that acceptance is becoming widespread. It is the goal of the National Down Syndrome Society to ensure that all people with Down syndrome are provided the opportunity to achieve their full potential in all aspects of community life."

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