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Down syndrome is a genetic disease caused by three major factors, genetics, chromosome formation and cell division. Through scientific research, scientists have made vast discoveries on how to "treat" people with the disease and how to help families cope with a child with Down syndrome. Through our research we hope to make more people aware of Down syndrome, how it is caused, how they can help and what is being done to treat people with the disease, so that one day it may be "curable. " Down's syndrome was discovered in the late 19 th century by John Langdon Down. His scholarly work published in 1866 earned him the recognition as the "father" of the syndrome. "Jerome Lejeune identified Down syndrome as a chromosomal anomaly. Down syndrome is an extra partial or complete 21 st chromosome, which results in the characteristics associated with Down syndrome" (Madnick 2). "It is characterized by low muscle tone, flat facial profile, oblique palpebral fissures, dysplastic ear, single deep crease across the center of the palm, hyper flexibility, dysplastic middle phalanx of the fifth finger, epicanthus folds-small skin folds on the inner corner of the eyes, excessive space between large and second toe, and enlargement of tongue in relationship to size of mouth" (Madnick 5). One of the causes of Down syndrome is genetics. "Genetics are grouped along rod-like structures called chromosomes.
Normally, the nucleus of each cell contains 23 pairs of chromosomes, half of which are inherited from each parent" (Madnick 2). However, in Down syndrome, the cells usually contain not 46, but 47 chromosomes; with the extra chromosome being a number 21. "Because 95 percent of all cases of Down syndrome occur because there are three copies of the 21 st chromosome, it is referred to as "trisomy 21 " (Madnick 2). Chromosomes can be studied by examining blood or tissue cells. Individual chromosomes are identified, stained, and numbered from largest to smallest; this visual display is known as a karyotype. Another way that Down syndrome is caused is through cell division; usually through an error in non-disjunction.
However, two other types of chromosomal abnormalities, mysticism and translocation, are also implicated in Down syndrome-although to a lesser extent. Regardless of the type of Down syndrome, all people with Down syndrome have an extra 21 st chromosome, which adds more genetic material, altering the course of development. "Nondisjunction is a faulty cell division which results in an embryo with three number 21 chromosomes instead of two. Prior to, or at, conception, a pair of number 21, in either the sperm or the egg, fail to separate" (Madnick 3). As the embryo develops, the extra chromosome is replicated in every cell of the body. This faulty cell division is responsible for 95 percent of all cases of Down syndrome. It has been postulated that some environmental factors may be implicated in nondisjunction.
However, the causes of nondisjunction are unknown even with years of research. Mosaicism occurs when nondisjunction of the 21 st chromosome takes place in one of the initial cell divisions after fertilization. "When this occurs, there is a mixture of two types of cells, some containing 46 chromosomes and some containing 47. Those cells with 47 chromosomes contain an extra 21 st chromosome" (Madnick 3). Because of the "mosaic" pattern of the cells, the term mysticism is used.
Some research has shown that individuals with mosaic Down syndrome are less affected than those with trisomy 21. However, broad generalizations are not possible due to the wide range of abilities that people with Down syndrome possess. The last cause of Down syndrome is translocation. Translocation is a different type of chromosomal problem and occurs in only three to four percent of people with Down syndrome. "Translocation occurs when part of the number 21 chromosome breaks off during cell division and attaches to another chromosome. While the total number of chromosomes in the cells remains 46, the presence of an extra part of the number 21 chromosome causes the features of Down syndrome" (Madnick 3). As with nondisjunction trisomy 21, translocation occurs either prior to or at conception.
Translocation is not linked to maternal age, unlike nondisjunction. "Most cases are sporadic, chance events. However, in about one-third of cases, one parent is a carrier of a translocate d chromosome. For this reason, the risk of recurrence for translocation is higher than that of nondisjunction" (Madnick 3). Genetic counseling can be sought to determine the origin of the translocation. Down syndrome is a disease that is very hard to understand. When a child has Down syndrome there are certain characteristics that set the child apart form other children.
When we take a look at Down syndrome we need to understand that the physical features will be different than that of a normal developing child. The tiresome 21 that cause Down syndrome affect many areas of development. The area of development that are seen most of the time is the physical features meaning the face and their height. When a person has Down syndrome they will look slightly different. The childs head will be smaller than average. The nose tends to be smaller and the bridge of the nose seems to be somewhat low.
The eyes are slightly different from the average. The child with Down syndrome their eyes are slanted upwards. The childs mouth is relatively small and the roof of the mouth a bit short. These are just a few characters of a child with Down syndrome. Theses are different but they are very special children and should be treated the same as an average child. The next feature that deals with the physical characters is the childs growth.
The childs height is affect by the disease a great deal. The growth of a child with Down syndrome tends to be short and their built is stocky. (Smith 31) Their growth up to age four is slightly behind average. Then it decreases each year. The height is different when we take a look at boys and girls. The average height of a boy with Down syndrome is about the same height of that of eight- year old child. That is about the tallest the boy will get.
The average height of a girl with Down syndrome is about the same as a ten-year old girl. The average height of a man with Down syndrome is about five feet tall. The average height of a female is about four foot seven. Theses are the average but a child could access these levels. Babies with Down Syndrome can have special medical problems. Although some of these problems can be quite serious, medical treatments have improved so much that today the vast majority of babies with Down Syndrome can grow up healthy and active.
Extra genetic material can cause a wide variety of medical conditions, including heart, intestine and eye problems. Over forty percent of babies with Down Syndrome are born with heart defects. For decades these defects meant early death, but today advanced medical treatment with drugs and life-saving surgery are common, even almost routine. There are several types of heart defects. The most common is called an Endocardial cushion defect.
This means that the walls between the two upper chambers and the two lower ones of the heart, as well as the valves between...
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Research essay sample on Child With Down Syndrome People With Down Syndrome
