The Characteristics of Down Syndrome, a Genetic Disorder

Recently I have heard about and seen people with Down's syndrome, actually I didn't knew anything about them and why they all are alike and have certain disabilities. One thing I knew is that it is and it was a great misfortune as for them as for their parents and relatives. Here are some of my and others ideas about what is the Down's syndrome, how it could be described and of course cause of that illness.Down syndrome is a genetic disorder. People with Down syndrome are humans who have recognizable physical features and limited intellectual abilities which are due to the presence of an extra chromosome 21. It is due to abnormal development of the fetus.

Scientists are still learning about what causes this extra genetic material and exactly how it causes the problems of Down syndrome. "The estimated incidence of Down syndrome is between 1 in 1,000 to 1 in 1,100 live births. Each year approximately 3,000 to 5,000 children are born with this disorder. It is believed there are about 250,000 families in the United States who are affected with Down syndrome". (Jean Etienne Dominique Esquirol: Des maladies mentales consideres sous le rapport mdicale, hyginique et mdico-legal translation from Russian language, page 234)

It is almost certain that there have always been people with Down syndrome. The earliest recorded representation of a person with the characteristic features of the condition was found in Aacchen, Germany, painted in about 1505.Then only in 1866 Dr John Langdon Down (1828-1896), an English doctor working in Surrey, first described the characteristic features of the syndrome. (Mark Selikowitz "Down Syndrome the facts" 27 page) "Down's syndrome is one of the most common causes of mental retardation. It is due to trisomy of chromosome 21. This additional chromosome, because of the certain proteins to be formed in the cell. This disturbs normal growth in the body of the fetus. Its main features are mental retardation and associated characteristic facies and habitus."  Many theories have been developed, but it is

Order custom essay The Characteristics of Down Syndrome, a Genetic Disorder with free plagiarism report

450+ experts on 30 subjects Starting from 3 hours delivery

Get Essay Help

not known what actually causes Down syndrome. It has been known for some time that the risk of having a child with Down syndrome increases with older age of the mother; i.e., the older the mother, the greater the possibility that she may have a child with Down syndrome. However, most babies with Down syndrome (more than 85 percent) are bom to mothers younger than 35 years. Some investigators reported that older fathers may also have increased risk of a child with Down syndrome. It is well known that the extra chromosome in trisomy 21 could either originate in the mother or the father. Most often, however, the extra chromosome is from the side of the mother.

Although humans with Down syndrome have certain physical characteristics, generally they are more similar to the average person in the community. Not every child with Down syndrome has all the characteristics; some may only have a few, and others may show most of the signs of Down syndrome. Some of the physical features in children with Down syndrome include "flattening of the back of the head, slanting of the eyelids, small skin folds at the inner corner of the eyes, depressed nasal bridge, slightly smaller ears, small mouth, decreased muscle tone, loose ligaments, and small hands and feet".(Mark Selikowitz "Down Syndrome the facts" 27 page )

About fifty percent of all children have one line across the palm, and there is often a gap between the first and second toes. The physical features observed in children with Down syndrome usually do not cause any disability in the child. "The affected person is usually small, 145-160 cm for adults. Birth weight usually 10-20 % below normal. Mental retardation (100%) becomes evident to parent at end of first year of life. The intelligence quotient in adults is most often below 50. Usually, child is happy, affable, and affectionate; walking: speech and toilet training delayed until 2 to 3 years of age. Delayed puberty, early menopause."

All humans with Down syndrome have an extra critical portion of chromosome 21 in their cells. But the amount of chromosome 21 present, and the way in which the error comes about, can take one of three forms.1. Trisomy 21. The vast majority of children with Down syndrome (95%) have an extra whole chromosome 21 in every cell of their body. This is called "trisomy 21". This is the commonest form of Down syndrome in children born to mothers of any age. It results from one of the parents giving two number 21 chromosomes, rather than the usual one, to the child through the egg or the sperm.

In about 4 percent of cases, Down syndrome is due to the presence of an extra part, rather than the whole, of chromosome 21. This occurs when the small top portions of chromosome 21 and another chromosome break off, and the two remaining portions stick to one another at their exposed ends.

Mosaicism. In about 1 % of children with Down syndrome, there an extra whole chromosome 21 in only a proportion of their body cells. The rest of their cells are normal. These individuals are said to exhibit mosaicism, because the cells of their body are like mosaic made up of different pieces, some normal and some with the extra chromosome. (Mark Selikowitz "Down Syndrome the facts" 36-42 pages)

As I think growth and development is unique to every child. Children learn to walk, run, use their hands and eyes, understand language, speak, think, and solve problems at different areas of their state. Children with Down syndrome do all of these things too. However, children with Down syndrome generally grow more slowly, learn slowly, and have a lot of troubles with critical thinking and judgments than other children. They sometimes are very impatient and get angry.

Children with Down syndrome generally should not be compared with other's children development. There have been enormous changes for people with Down syndrome over two past decades. Children with the syndrome now usually live at home and enjoy the love and warmness they receive from their families. They benefit from early teaching and special help through the school years. Included in everyday activities, they are socially more competent, and their needs for recreation and friendship are increasing, as are opportunities for expansion in community support services providing help to parents. I think there is no doubt that parents can look forward to a brighter future for their child than ever before.

Don't let plagiarism ruin your grade

Run a free check or have your essay done for you

Check my essay Hire Writer