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All children that are born with Downs Syndrome (previously called mongolism) have a common characteristic appearance and may also share similar congenital birth defects. Dr John Downs, of whom the condition is so named after, found that children who were born with these similar characteristics and that after testing were complete. It was found that there was a common chromosome abnormality, which is known as Trisomy 21 (Cunningham, 1996). Every pregnant woman is at risk of having a Downs Syndrome child. For example 1 in 1, 000 women who are 28 yrs will give birth to a child with this condition. However, the risk is much greater with a woman who is 38 yrs, increasing the risk by approximately 1 in 200 births.
Until recently, it was thought that a womans age was the only indicator to the risk involved. However, advances in medical practise can now carry out tests out by looking at a womans hormone and protein levels during pregnancy. Also with the information of the expectant mothers age and the use of maternal screening, two thirds of Downs Syndrome infants can be identified whilst still in the womb. Research into the origins of Downs Syndrome has been carried out worldwide all with one common question in mind; is the condition genetic, thus making it hereditary? However, research that has been carried out has found, that children born with this condition have the same genetic makeup as a child born without the condition.
However, there is one difference and that is a child born with Downs Syndrome, will have an extra chromosome. By having just one chromosome extra is enough to tip the finely tuned balance of the human body and will in turn produce physical and intellectual characteristics that are found in Downs Syndrome. It is commonly known that genes are passed from parent to child. And those most have two copies of every gene. In general one copy is passed on from both mother and father at the time of conception.
The genes are made up of DNA (deoxyribonucleic acid). The arrangement of chemicals in the DNA strand is different for every gene (Cunningham, 1996). The genes are grouped together in long thin, thread like strands called chromosomes. Therefore, it is these chromosomes that carry the essential information, which will determine how we look, how healthy we are and whether there will be congenital defects when we are born. This study will look at the effects of Downs Syndrome by drawing upon a number of resources of information such as the Internet, pamphlets, books and an actual case study of a child who suffers with the condition. Genetics of Downs Syndrome Downs Syndrome occurs when a child is born with the extra chromosome 21 materials in their cell structure.
Downs Syndrome is also known as Trisomy 21. Trisomy means that there are 3 (tri) copies of chromosome (some) 21 (see figure, 1). There are also three types of Downs Syndrome 1) Regular Trisomy 21 - also known as Free or Standard Trisomy 21. In which all the cells carry the extra chromosome 21. 94 % of people, who suffer from Downs Syndrome, suffer from this type. 2) Translocation is where the extra chromosome 21 materials are attached to another chromosome. And only 4 % of sufferers have this type of the condition (see figure, 2). 3) Mosaic is where only some of the cells have an extra chromosome 21.
This type is very rare and that only 2 % of sufferers will have this type of the condition (Cunningham, 1996). It is thought that chromosome 21 only contains 1 % of the bodies genes. Therefor, Downs Syndrome arises from a change in gene quantity rather than a quality of genes. It is not known why this condition occurs; it is for this reason that it is so different from other genetic disorders such as Cystic Fibrosis and Sickle Cell Anaemia.
Which, the inheritance of these diseases or disorders, can be traced back through family medical histories. However, Downs Syndrome can only be traced, through families of, less than 1 % of people with the condition. These people all have rare types of Translocation (see bullet point 2, for explanation of this type) (Carr, 1995). This could suggest that it is very unusual for parents to have more than one Downs Syndrome child or for relatives of these parents to also have a child with the condition. Regular Trisomy 21 occurs when an unusual cell division has taken place, which has produced either an egg or a sperm with 24 chromosomes instead of 23.
When this egg or sperm fuses with an ordinary egg or sperm, the first cell of the developing baby has 47 chromosomes instead of 46. This will then leave the childs cells with 47 chromosomes. There is no way of predicting whether a person is more or less likely to produce eggs or sperm with 24 chromosomes (Carr, 1995). The extra chromosome can come from an uneven division of the chromosomes (called non-dysfunction) at either the first or second meiotic division, in either parent. At present it is suggested that one child with Downs Syndrome is born in every 1000 total births. Also there are more conceived than are born, because the chance of miscarriage is higher if the foetus has Downs Syndrome (WHO, 1989).
As yet the reason why older women are more likely to have a child born with this condition, is still unknown. However, there are two current theories available which attempt to explain why it does happen. Carr (1989) suggests that all women have a certain amount of extra ovum, which contain the extra chromosome. It is these extra ova's which are more likely to be used last and towards the end of a womans reproductive life. Another theory looks at the rate of Trisomic conceptions are the same at all ages, but that affected pregnancies are more likely to go full term in older women, rather than end in miscarriage? The assumption of both these theories is that the body recognises that this is a late pregnancy and may be the last or only pregnancy that the woman can achieve.
Thus the body tries to make sure the pregnancy goes to full term (Cunningham, 1996). Parents with one child, who suffer with this condition, are usually informed that the chance of conceiving another child with the Down syndrome condition is about 1 in 100. Very few families are known to have more than one child with Downs Syndrome. So in reality the chance is probably a lot less than this statistic. Selikowitz (1997) found that 4 % of Downs Syndrome does not have an extra or separate chromosome 21. But have an additional part of chromosome 21, which is attached to another chromosome.
This usually arises when the small arms of the chromosome 21 and other chromosomes break and that the two remaining long arms join together at their exposed ends. It is this process of chromosomes breaking and then fusing back together which is known as Translocation, because the chromosome material has transferred its location. It must be pointed out that the features and characteristics of Downs Syndrome are no different from those of a child with regular Trisomy 21 (Selikowitz, 1997). In two thirds of people with Downs Syndrome due to a Translocation, the actual Translocation was an isolated event during the formation of the individual egg or sperm involved at the time of conception. As with Trisomy 21, there is no known cause why this occurs. It cannot be predicted and is not a result of anything the parents have or not done.
In one third of sufferers who have a Translocation type Downs Syndrome, it has been assumed to be inherited from one of the parents. The parent will already have two 21 chromosomes in each cell, but one of them will be attached to another chromosome. This is known as a balanced Translocation, thus the parent is the carrier of the Translocation. It is important to realise that there is no loss or gain of genetic material. Also, it is vital to point out that, that because such parents have the usual amount of genetic material, they have no traces of the Syndrome themselves and will never suffer from the condition. The only way these parents can ever be made aware of the risk they carry, is if they allow a Geneticist to scrutinise both sets of the parents genes (Selikowitz, 1997).
However, people who carry the Translocation ovum or sperm, it is then possible for it to be passed on both with the Translocation and the free chromosome 21 egg or sperm. Thus, the conceived child will be born with Downs Syndrome. As there is only 4 % of people who suffer with this type of Translocation Downs Syndrome and one third of this group have inherited. Only about 1 % of sufferers have actually inherited the syndrome (Selikowitz, 1997).
Unlike regular Trisomy 21, Translocation occurs equally and frequently no matter what age of the parents (Carr, 1995). When neither of the parents is a carrier, the Translocation is an isolated event nor it remains a remote chance of it happening again (genetics quote less than 1 %). However, Translocation carriers can produce children who will in turn become carriers themselves. Also they may produce children who will suffer with the said condition and in certain cases show no signs of cell arrangement at all (Selikowitz, 1997). There is no difference in the features or ability levels of people with regular Trisomy 21 and Translocation Downs Syndrome. The only way of knowing which type a person has, is by the study of their blood samples followed up by a study of their chromosomes (Cunningham, 1996).
However, sufferers of Mosaic Downs Syndrome have an extra chromosome 21 in only some of their cells. Therefore they have a mixture of Trisomic cells and ordinary cells. It is important to point out that, the mixture can vary between very few to nearly 100 % Trisomic cells. However, depending on the proportion of Trisomic cells and which parts of the body which contain these cells, individuals may be less affected both in their physical features and in their ability level than those with regular Trisomy or Translocation. As for all the types of Downs Syndrome, it is not possible to say at birth how affected a person will be. It is only time that will tell, as the child develops (Cunningham, 1996).
Mosaicism happens when an egg and sperm fuse together at the time of conception. As the cell divides and multiplies by ordinary cell division, a chromosome can go astray and a single cell with an extra chromosome 21 is formed. This cell continues to divide and multiply by ordinary cell division together with the non-Trisomic cells and a mixture of cells is formed and produced. As with the other types of Downs Syndrome (apart from where a parent is the carrier) there is no known reason why Mosaic Downs Syndrome occurs. It has also been found to happen often and equally in parents of all ages (Cassell, 1996). EDUCATION FOR DOWNS SYNDROME.
Many children who suffer with Downs Syndrome actually enjoy attending their pre-school play group and it is fundamental that the basic building blocks to prepare children for the inclusion into mainstream school, can be learnt in these environments. These areas will include social inclusion, motor development, and self-help, speech and language development. In the early years of the childs life, the primary aim is social inclusion. This will allow the child or children to mix with other children in their local community (which is socially beneficial to all the children in that community). By this early socialising of the child will provide the early opportunities to learn from typically developing children of that age, who set the expectations for that age-appropriate behaviour and achievement.
However, many children who suffer from Downs Syndrome, will no doubt be at a lower development, social and emotional level due to their learning difficulties. They also may need additional help and support. Moreover, it has been found that, children with Downs Syndrome will and do not learn well from incidental learning and will not pick up conventions intuitively, as do their peers. So their understanding of the world will be a great deal less advanced and their behaviour may be on even par with children a lot younger than themselves.
It must also be pointed out that, for any child with or without Downs Syndrome, it is much harder to make progress in cognitive areas, until they are able to behave and interact with others in a socially acceptable way and understand to respond and behave appropriately to the immediate environment. The focus of additional help and support in the early years should therefore be on learning rules for normal social behaviour (Alton, 1998). It is equally important to point out that, there are no behaviour problems unique to children with Downs Syndrome (Alton, 1998). However, much of their behaviour will be related to their level of development.
It is with this view, that when problems do occur, they are generally similar to those seen typically developing children of a younger age. In addition, children with Downs Syndrome have grown up having to cope with more difficulties than many of their peers. Much of what they are expected to do in their everyday lives will have been much harder to accomplish due to their learning difficulties, speech and language problems, auditory short-term memory, motor co-ordination, and shorter concentration spans as a whole. The thresholds that trigger problem behaviour may therefore be lower than their typically developing peers. For example, children with Downs Syndrome are more likely to become frustrated and over anxious more easily. Thus, a child with Downs Syndrome does not lead inevitably to behavioural problems, but the nature of the difficulty makes them more vulnerable to the development of behavioural problems (Alton, 1998).
A particular aspect of problem behaviour is the use of avoidance strategies. Research has shown that, like many pupils with special needs, pupils with Downs Syndrome tend to adopt such strategies, which undermine the progress of their learning. Some pupils tend to use anti-social behaviour to distract adult attention and in doing so avoid learning. It is also recognised that they seem to be prepared to work only on tasks, which fall within a very narrowly defined cognitive range (Alton, 1998). It is suggested that it is important to remain alert to the possibility of avoidance and to separate immature behaviour from deliberately bad behaviour. Also, to ensure that the childs developmental, not chronological, age is taken into account together with their level of oral understanding.
Thus, any reward offered also has to be taken into account of these factors (Alton, 1998). Many children with Downs Syndrome have shorter concentration spans than their peers. They also have more difficulty in processing input from more than one sense, at any more than one time for example, copying from a white board and listening to the teacher at the same time. Thus, this factor alone inhibits their ability to focus and learn. These difficulties are particularly apparent in the early years of learning and many children with Downs Syndrome may be very destructible, thus flit from one activity to another. This means that the less focused and the more informal the situation is, the more difficult it will be for the child to channel attention into one activity for any length of time.
However, children with Downs Syndrome do respond well to structure and routine, thus increasing their ability to learn. Teaching children with Downs Syndrome, routine and structure of their day, along with the aid of strong, clear visual clues. For example, photographs and objects with the appropriate reference can help a child with Downs Syndrome learn. By using these clues a child with Downs Syndrome can begin to understand their living environment better. Also, it has been noted that it is particularly useful in teaching appropriate behaviour for particular sessions and occasions, activities and predicting the next activities difficulties with understanding verbal explanations, also instructions are also overcome (Alton, 1998).
Activities that depend on gross, and fine motor co-ordination skills, such as sitting, crawling, walking, running, manipulating toys, feeding and drinking independently. These activities all increase a childs opportunity to find out about their world in which they live. Therefore, it is important to bear in mind that any delay in motor development in early learning years, is more likely to restrict cognitive development. Children with Downs Syndrome who tend to have lax muscle tone (...
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Research essay sample on People Who Suffer Downs Syndrome
