system
Given the following post, respond as if you're commenting on Reddit:
human
When making a clone of an organism, is it possible that different genes get expressed?

Or are they always 100% identical?
gpt
For the standard nucleus transplantation method, all the genes should be expressed the same, but the conditions of gestation and early life can mean that there are differences, so the organism is unlikely to be completely identical even with identical genes. There's also slight variation used with the donor egg, which contributes the mitochondria for the new organism, and any random mutations that may arise either by complete chance or due to differences in the environment.