The Common Type Of Down Syndrome Essay

1884 Words May 13th, 2016 8 Pages
Down syndrome is one of the most common genetic disorders. Down syndrome is a genetic disorder where a person is born with an extra copy of chromosome 21. Down syndrome is a form of mental retardation. In the United States about 4,000 children are being born with this condition annually. One in about every 900 births is effected, making it the most common birth defect. There are three genetic variations that cause this disorder: trisomy 21, Mosaic Trisomy 21, or Translocation Trisomy 21. There are many ways in how this disorder can affect the body. Trisomy 21 happens when an egg or sperm comes in with an extra copy of chromosome 21, then when an embryo is formed and starts to develop the chromosome is replicated in every single cell of the embryo. Trisomy 21 is one of the most common type of Down syndrome. About 92% of people with down syndrome have this type. People with Trisomy usually have more of the physical problems. Mosaic Trisomy 21 occurs when an egg or sperm comes with an extra chromosome 21. In mosaic Trisomy 21 occurs in 2-3% of people with down syndrome. Mosaic Trisomy produces a wide range of physical problems as well. Translocation Trisomy occurs when the extra copy or piece of chromosome 21 attaches to another chromosome. Usually if it happens it attaches itself to chromosome 14. About 3-4% of people have Translocation Trisomy down syndrome. Anyone can be born with down syndrome because it is an event that occurs at random. Even though down syndrome can be…

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