1. By Bailey Mulford and Rachel Lanaghen
Down’s Syndrome
By Bailey Mulford and
Rachel Lanaghen

2. OVERVIEW
Down’s syndrome, named after Dr. John Langdon Down, is a chromosomal disorder. It is caused due to trisomy, the presence of an extra copy, of the 21st chromosome.

3. PHYSICAL SYMPTOMS Typically have a very round face
“Almond-shaped” eyes
Brushfield spots (white spots on the iris)
Flat bridge of the nose
Protruding tongue due to a small oral cavity and enlarged tongue)
Shorter neck
Congenital heart defects
Large space between the big toe and second toe
Muscle hypotonia (poor muscle tone)
Most exhibit mild to moderate mental retardation

4. INHERITANCE Down’s is inherited one of three ways…
Non-disjunction (95%) – during meiosis, a gamete ends up with 24 chromosomes rather than the usual 23
Translocation (3-4%) – where one of the parents has chromosome 21 attached to another chromosome, usually chromosome 14
Mitotic Errors (<3%) – in early development of the fetus, the chromosome 21 pair fails to separate in anaphase

5. STATISTICS
Down’s Syndrome is estimated to be anywhere from 1 in 800 to 1 in 1000
As of 2006, the estimate was 1 in 733 live births
Maternal age has a strong influence on if the baby has a third copy of chromosome 21. As shown in the graph to the right, as the age of the mother increases, the instances with Down’s increases accordingly.

6. PROGNOSIS AND TREATMENT
Down’s Syndrome can be detected through a number of prenatal screening techniques including…
Amniocentesis- sample of amniotic fluid
Chronice villus sampling (CVS)
Percutaneous umbilical blood sampling (PUBS)
Triple screen- measures protein and hormone levels
Quad screen- measures protein and hormone levels
AFP/free beta screen- measures protein levels
PAPPA screen- uses ultrasound that measures protein levels
These tests are 90-95% accurate with 2-5% false positives.
At present, there are no cures or treatment for Down’s Syndrome. However, many of the symptoms such as congenital heart failure may be treated with various medications.

7. LIFE EXPECTANCY
Individuals with Down’s Syndrome have a slightly higher morbidity rate due to impaired immune responses, increase in congenital heart disease, and airway obstructions. The estimated lifespan is 49 years, which is a dramatic increase from the 24 years of age in 1980.
75% die in embryonic or fetal life
15% die within the first year after their birth
50% live past 50 years of age

8. LIVING WITH DOWN’S SYNDROME
From the early 20th century through the 1960s many people with down syndrome were put into institutions, largely excluded from the rest of society.
Now that scientists and doctors better understand this disorder a more humane policy of inclusion has been initiated.

9. Inclusion
Inclusion is a strategy that works at meeting the needs of people with down syndrome as much as possible in public education and developmental institutions. There are many academic and social benefits for both students with the disorder and students without it when they are given the opportunity to learn and grow together.
New Friendships
Non-disabled students are more appreciative of differences
Students with disabilities are more motivated when they are pushed to their potential like any other person

10. LIVING WITH DOWN SYNDROME
Today…
Most children with down syndrome go to public school and participate in many of the same activities as non-disabled students (although some do perform better in specialized programs)
Many go to college
Many live in semi-independent housing and hold jobs
The National Down Syndrome Society is trying to expand post secondary opportunities by developing a model school/program especially fitted for people with down syndrome.
Their fertility is significantly decreased (only 3 recorded fathers in history) and there is no evidence to support that this a hereditary disorder.
Most people with this disorder live happy, rewarding lives. Gradually mainstream society is beginning to understand the unique and contributions and talents they have.

11. Resources
Local support groups and instructional programs for new parents and relatives can be found through these national organizations:
National Down Syndrome Congress
National Association for Down Syndrome
National Down Syndrome Society
Band of Angels Foundation

12. WORKS CITED
“Down’s Syndrome”, Wikipedia,
“Down’s Syndrome”, BioZone, pg.203
“Down Syndrome” eMedicine