When is child is born with trisomy, when did the mutation occur?
When a child is born with trisomy or Down Syndrome, the mutation occurs during meiosis or the process of cell division. In trisomy, the chromosome number 21 in an egg or sperm cell fails to separate. Here's the link for more information: http://learn.genetics.utah.edu/content/disorders/whataregd/down/.
The mutation occurred during the meiosis stage. For more information about trisomy, visit http://www.livingwithtrisomy13.org/.
Trisomy is one genetic abnormality wherein three copies of certain chromosomes are produced instead of two. This is also a type of aneuploidy. The mutation in trisomy occurs during meiosis.