No, an organisms' genes cannot 'turn off' at any point. They are not mechanical in any way.
By introducing chemicals into the area that (thing) that they want to alter the genes of, they can "turn off" or "turn on" different genes that were dormant or active, but pre-existed in the subject
A lac repressor turns off the lac genes by binding to the operator.
it likes chicken then not its like turning it off and on
Proteins
Clever mechanisms turn genes off and on so that they only function when there is a need for their services
corepressor
The epigenome refers to the markers that turn on and off specific genes. The markers themselves are named according to their chemical composition, ie. methyl-markers.
DNA Manipulation
The function of DNA in a cell is to code the way proteins turn genes on or off, and to carry genetic material.
Genes are regulated through a number of ways. Some can be regulated by the environment you're in. For example, if you're in the sun a lot, genes will get turned on or up to increase the production of skin pigmentation so you get tanned. When you stay out of the sun, the genes turn off and your skin gets lighter.
Genetic Engineering
It depends what the parents genes are.