Down's Syndrome

You might know, or have seen somebody with Down’s syndrome, but in this video, you are going to learn what it is and why it happens. Down’s syndrome is caused by a change in the DNA. You probably remember that any change in the structure or the amount of DNA of an organism is called a mutation. Mutations are caused by mutagenic agents, like some chemicals, or ultraviolet light for example. If a mutation happens in a somatic (body cell) only this cell and it’s daughter cells will be affected. If a mutation happens in a sex cell (gamete) and fertilization happens, then all of the cells of the embryo (foetus) and a baby will carry this mutation. This is what happens in Down’s syndrome.