Deletion is a type of mutation involving the loss of genetic material. It can be small, involving a single missing DNA base pair, or large, involving a piece of a chromosome.
As such, the nucleotide sequences found within it are subject to change as the result of a phenomenon called mutation. ... Depending on how a particular mutation modifies an organism's genetic makeup, it can prove harmless, helpful, or even hurtful.
47,XYY syndrome is caused by the presence of an extra copy of the Y chromosome in each of a male's cells. As a result of the extra Y chromosome, each cell has a total of 47 chromosomes instead of the usual 46.
