Characteristics of Down's Syndrome

Down syndrome is also known (or formally) Mongolian disease and is the most common chromosomal abnormality in the United States. More than 350,000 people have this situation. It is caused by an additional chromosome 21. This is also known as trisomy 21. To determine that additional chromosome 21 affects Down's syndrome, there are 46 chromosomes in each cell. There are three copies of this chromosome. It is caused by a unit error called nonseparation. The other two types are mosaic and translocation.

Mosaic is the least common form of Down's syndrome, accounting for only about 1% of all Down's syndrome cases. Studies have shown that Down's syndrome may be less characterized by Down syndrome than other types of Down's syndrome patients. However, people with Down Syndrome have broad capabilities and can not be generalized. In translocation, the total number of intracellular chromosomes is still 46 in about 4% of cases of Down's syndrome; however, extra whole or part of the copy of chromosome 21 is bound to another chromosome, usually chromosome 14 doing. The presence of all or a portion of chromosome 21 additionally leads to a distinguishing feature of Down's syndrome.

In recent history, advances in medicine and science have enabled researchers to study the characteristics of Down's syndrome patients. In 1959, French doctor Jérôme Lejeune recognized down syndrome as chromosomal abnormality. Mr. Lejeune observed 47 individual cells in Down's syndrome, not 46 chromosomes common to each cell. It was later determined that additions or all copies of chromosome 21 resulted in features associated with Down's syndrome. In 2000, the international scientific team identified and cataloged about 329 genes of chromosome 21, respectively. This achievement opens the door to tremendous progress in Down's syndrome research.

Children with Down syndrome have a distinctive appearance that is widely recognized. Their heads are smaller than usual and may have abnormal shapes. Other notable features of Down's syndrome are: flat nose, prominent tongue, upwardly inclined eyes, short hands and fingers, and one wrinkle in the palm. (Http://www.mamashealth.com) Down Syndrome affects the ability of children to learn in various ways, but most suffer from mild to moderate mental retardation. Children with Down Syndrome can learn and grow skills throughout their lifetime. They only achieve their goals at different speeds. People mistakenly believe that people with Down's syndrome often have "static" or predefined learning abilities. This is absolutely not true. People with Down's syndrome are now known to develop throughout their lifetime and need to be treated accordingly