By: Jessica Blayer Tracy Pawluk Erin Sand Down Syndrome By: Jessica Blayer Tracy Pawluk Erin Sand

Background Down syndrome is a common genetic variation which usually causes delay in physical, intellectual and language development Down syndrome is a genetic disorder caused by the presence of an extra 21st chromosome It is named after John Langdon Down, the British doctor who described it in 1866

Background Down syndrome is one of the leading clinical causes of cognitive delay in the world and it is not related to race, nationality, religion or socio-economic status The incidence of Down syndrome is estimated at 1 per 800 to 1,000 births Of all children born in this country annually, approximately 5,000 will have Down syndrome

Characteristics Individuals with Down syndrome can have a lower than average cognitive ability, often ranging from mild to moderate mental retardation A small number of individuals have severe to profound mental retardation Physical Characteristics single transverse palmar crease (a single instead of a double crease across one or both palms) almond shaped eyes caused by an epicanthic fold of the eyelid shorter limbs poor muscle tone protruding tongue

Other Health Problems Approximately half of children with Down syndrome are born with some type of heart defect These heart problems can be life threatening and can require surgery in early infancy More likely to develop leukemia Because of abnormalities in their immune systems, people with Down syndrome are much more susceptible to infectious diseases As people with Down syndrome age, they have a greatly increased risk of dementia Signs of dementia are often seen before age 40 in people with Down syndrome Other health conditions are also commonly found in people with Down syndrome, including gastrointestinal blockage, thyroid problems, hearing loss and poor vision

Screening in Utero Most pregnant women have a blood test done around the 15th week of pregnancy to screen for down syndrome The test looks at three chemicals found in the woman’s blood to estimate the risk of Down syndrome in her fetus The likelihood of giving birth to a child with Down syndrome increases with maternal age However, 80% of babies with Down syndrome are born to women under 35 years of age Both men and women can pass the genetic translocation for Down syndrome on to their children However, in most cases Down syndrome occurs due to faulty gamete cell division and it is not inherited

Screening Video http://video.on.nytimes.com/?fr_story=75b21d45037ddde30bf24171111b1ab53bebc333

Genetics

Brain Differences in Brain some of these differences include embryonic simplicity abnormal convolutions reduced weight abnormal shape Differences in the brain are not apparent at birth, but differences appear within the first months of development

Brain In contrast, the brain of a person with Down syndrome lacks surface complexity The frontal lobes may have defective tissue development This is important because the frontal lobe controls fine motor movements, lips, tongue, and vocal cords There is also compression of the occipital lobes and a smaller cerebellum and brain stem In one study, 20-50% fewer neurons were found in the visual cortex of people with Down syndrome

BRAINS!! Brain of a person with down syndrome Brain of “Average” Person

Neurobiology Studies suggest selective impairment of functions of the hippocampus, prefrontal cortex, and cerebellum Hippocampus is most impaired of the three Hippocampus functions that have been impaired in a person with Down syndrome include exploration, context learning, and spatial cognition

Treatments There is no medical treatment for Down syndrome that will provide a cure Children with Down syndrome do benefit from medical help and early interventions, starting in infancy Physical Therapy, Occupational Therapy, Speech/Language Therapy

Educational Implications Most students with Down syndrome receive special education services and are placed in self-contained classrooms High-functioning students with Down syndrome can benefit from inclusive classroom settings Inclusive settings can offer students social, academic, and behavioral benefits Students who have the opportunity to be placed in inclusive settings often develop higher verbal and language development then those who are not

Educational Implications – Modifications & Accommodations Repetition of material is often needed to reinforce what is being presented Teachers can also adapt materials to make learning easier and more appropriate Students with Down syndrome often learn more efficiently when visuals/manipulatives are used because they often have problems with short-term auditory memory Additional deficits in working memory are problematic because this plays an important role in developing language skills in acquiring and attaining vocabulary

Educational Implications – Transition/Living Transition plans should start to be written when students turn 14 and complete plans should be designed by age 16 Options can include academic programs, vocational/training programs, or a combination of both Living arrangements are determined by the level of adaptive skills the student has Arrangements can include at home with the family, in student housing, or in group homes

Future Outlook Life spans have increased dramatically for people with Down syndrome In 1929, a baby born with Down syndrome often didn't live to age 10 Today, someone with Down syndrome can expect to live to 50 and beyond This age continues to rise because of early interventions and better care

References: Alton, S. (2001). Short-term Auditory Memory. DSA (UK) Journal, Winter, Issue 95. Bosworth, D. (2001). Benefits to students with down syndrome in the inclusion classroom K-3. Towson University Website: http://www.he.net/~altonweb/cs/downsyndrome/index.htm?p age= Bosworth.html Capone, G.T. (2004). Down Syndrome: Genetic insights and thoughts on early intervention. Infants and Young Children, 17(1), 45-48. Cold Spring Harbor Laboratory (2002). Down Syndrome. Your Genes Your Heath Website: http:// www.ygyh.org/ds/whatisit.htm (2006). Down Syndrome. Website: http://www.emedicinehealth.com/down_syndrome/article_em. htm

References: (2007). Down Syndrome. Website: http://www.en.wikipedia.org/wiki/Down_syndrome Mayo Clinical Staff (2007). Down Syndrome. Children’s Health Website: http://mayoclinic.com/health/down_syndrome/DS00182 Pennington, B.F, Moon, J., Edgin, J., Stedron, J., & Nadel, L. (2003). The neuropsychology of down syndrome: Evidence for hippocampal dysfunction Child Development, 74(1), 75-93. Uecker, A., Mangan, P. A., Obrzut, J. E., & Nadel, L. (1993). Down syndrome in neurobiological perspective: An emphasis on spatial cognition. Journal of Clinical Child Psychology, 22(2), 266-276. Van Cleve, S., Cannon, S., & Cohen, W. (2006) Part II: Clinical practice guidelines for adolescents and young adults with down syndrome: 12-21 Years. Journal of Pediatric Health Care, 20(3), 198-205.