Transmitted

__**Transmition**__
=== Down Syndrome is caused from Trisomy 21, which makes an extra copy of the chromosome 21, causing to an overproduction of certain genes and traits. Trisomy 21 causes 95 percent of all the recoreded cases of down syndrome. The 5 microDNA genes that are involved in Trisomy 21 lead to abnormal brain development, resulting in the mental and physical abnormalities.===

Normal human cells have 23 pairs of chromosomes, one from the mother, and the other from the father. individuals with Down SYyndrome have 3 copies of the chromosome, called Trisomy 21.
===Translocation is where the disorder is inherited from one of the parents (in more cases are very rare). Only about 4% of children with down syndrome are resulted in translocation. if the mother is a carrier of the down syndrome disorder, the chance of her child having it as well is about 12%, for the father it is only 3%.===


 * 88% is nondisjunction in the maternal gamete
 * 8% is from nondisjunction in the paternal gamete
 * More common in the older mothers, the possibility of a mother having a child with Down Syndrome at the age 35 and up are doubled.