Down Syndrome is a birth defect where there is a congenital malformation accompanied by moderate to severe mental retardation, and caused by a chromosomal abnormality. Down Syndrome is the most common genetic birth defect associated with mental retardation and occurs equally across all races and levels of society. The effects of the disorder on physical and mental development are severe and expressed throughout the persons life. (Genetic Disorders Source Book pg. 2)

Down Syndrome is characterized by a genetic defect in the chromosome pair 21. Normal cells in the human body, except the Ova and Sperm cells have 46 chromosomes. There are 44 autosomes and two sex chromosomes. Normal reproductive cells contain 23 chromosomes, 22 of them are autosomes and there is one sex chromosome. In all other no reproductive body cells, chromosomes occur in pairs. The

Not only do infants with Down Syndrome acquire motor skills at a slower rate, but there is a difference in the rate of development between infants with Down Syndrome who are institutionalized and those raised at home. (Motor Development of Down Syndrome Children pg. 3). Infants with Down Syndrome raised at home perform better than those in institutions. In one study, infants with Down Syndrome that stayed at home walked by five years of age, but only 60 percent of the children who were in institutions could walk by 6 years of age. One reason may be that children in institutions are treated in groups instead of individually, further limiting potential development. (Motor Development of Down Syndrome Children pg. 6)

The distinct physical characteristics of Down Syndrome include slanting eyes, slightly protruding lips, small ears, slightly protruding tongue, short hands, feet, and trunks, sometimes an unusual crease on the palm of the infants hand. Other characteristics such as congenital heart defects are common and nystagmus (involuntary movement of the eyes), enlarged liver and spleen also occur. Dry sensitive skin with decreased elasticity, umbilical hernia, short stature and short extremities are also characteristics of a patient with Down Syndrome. (Diseases Pg. 11) In 99 percent of the cases, there is mild to severe mental retardation. (Down Syndrome: The Psychology of Mongolism Pgs. 8-12) As the child grows, dental development is slow with abnormal or absent teeth. They also exhibit strabismus and occasionally, cataracts. The genitals develop poorly and puberty is delayed while the female may menstrate and become fertile.

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