Down\'s Syndrome

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Understanding and living with a child that has a syndrome is a heart breaking experience. Today over thousands of parents have to live with children that have down’s syndrome. Children are born frequently with this type of disorder. If someone close had a disorder would you understand what was going on or do you even know what I am talking about?
In 1866 the study of Down’s syndrome began. Physician John Langdon Down published and essay in England. The essay talked about a set of children who all looked alike and had mental retardation. These children also looked like people from Mongolia. In 1960 the name Down’s Syndrome became know to people. In the twentieth century there was speculation of a case of Down’s Syndrome. In the 1930’s Waardenburg and Bleyer came up with the theory that it might be chromosomal abnormalities. Jerome Lejeune and Patricia Jacobs found the trisomy of the 21st chromosome. Jerome and Patricia worked separately on the project.
A chromosome is a “thread-like structure composed of DNA and other proteins,” stated Len. Chromosomes are in every cell. They carry the gentic information to the cell to develop. “Genes, which are units of information, are ‘encoded’ in the DNA,” stated Len. A human is divided into mitosis and meiosis. Mitosis is were the body grows. In mitosis one cell converts to two cells and has the exact number as there parents. Meiosis occurs in the ovaries and the testicles. The one cell will split into two cells. When this happens cells have half the chromosomes the parents have.
Down’s syndrome or trisomy 21 is the most common autosomal trisomy. Mader stated “trisomy is having three of a particular type of chromosome,” and “autosomal is any chromosome other than the sex-determining pair.” Chromosome 21 usually has one copy and in Down’s Syndrome it has two. Down’s Syndrome has three copies in chromosome 21. In most cases the sperm had the extra 21 ch...