Yes, you're interfering with an extremely complex system. Are we really so naive to believe there is some exact 1:1 mapping of genes to traits, or even close to that? The fact I've heard things like "75% of DNA is useless" [1] seems like such a laughably naive statement I fear for the future of humanity.
[1] https://www.newscientist.com/article/2140926-at-least-75-per...