There is some research that shows that some people may be predisposed to cheating or have what is known as the cheating personality. These are people who are high on sensation seeking or risk-taking. They are addicted to the dopamine rush that comes with cheating behaviors. These are people who are also, for men, high in testosterone, high in drive, and are very likely to take risks. So, if someone likes risky behavior, they're more likely to cheat than those who tend to play it safe.
For instance, it's been known that politicians, athletes, and movie stars are predisposed to cheating. Again, these are people that are high on risk-taking and sensation seeking. They're the ones who are willing to risk everything to get in the spotlight and they're also likely to respond to sensation seeking activities. Of course, their are other elements that play into the cheating personality.
The family of origin is very important. That is, there seems to be a genetic component to cheating. They found, for instance, that seagulls inherit cheating behaviors. That is, seagulls who tend to unfaithful, as analysed by the DNA samples of their eggs, are more likely to give birth to progeny that is also going to be unfaithful. So there might be some genetic component to cheating as well, and that may be the way the response to dopamine and adrenaline produced by cheating behavior influences our behavior.
So, all of this is very complex, and although some people may be predisposed to cheating, of course, again, genetics isn't destiny. I think we're all able to learn to behave the way we want to behave and to maintain committed and stable relationships if we're motivated to.