Down Syndrome (Trisomy 21)

Down syndrome (Trisomy 21) Down syndrome is a genetic disorder that occurs when an individual has an extra chromosome 21 in them. Down syndrome can also be referred to as ‘Trisomy 21’. An English physician named John Landon Down first discovered Down syndrome back in 1862. This genetic disorder has been around since the 16th century and possibly even longer. The treatments for Down syndrome are not distinct as it depends on how severe the Down syndrome is. Down syndrome or Trisomy 21 was discovered in 1862 by an English doctor named John Landon Down. However, Down had referred the people with Down syndrome as mongoloids since they had similar physical features as those of Mongolian people. It wasn’t until 1959 when a French physician by the name Jerome Lejeune that discovered that people with Down syndrome had 47 chromosomes instead of the regular amount; 46. In addition, Down syndrome has been a genetic disorder for centuries. For example, “Throughout history
According to learn.genetics.utah.edu it states, “Down syndrome is typically caused by what is called nondisjunction. Nondisjunction happens when a pair of chromosomes fails to separate during egg (or sperm) formation. When that egg unites with a normal sperm to form an embryo, the embryo ends up with three copies of chromosome 21 instead of the normal two.” Down syndrome is sex-linked as it states in the quote that it is caused when a pair of chromosomes fails to separate during the egg formation causing it to obtain three copies of chromosome 21. Down syndrome is not caused by heredity unless in some cases it is translocation Down syndrome. Furthermore, Down syndrome is not a mutation. Down syndrome is only caused when an individual carries 47 chromosomes instead of