The KMT2D gene [1] is one example of a gene that I know of that regulates the express of other genes. Defects to this gene often result in the people having the Kabuki Syndrome [2].
If I remember correctly, Bert Hubert in his talk 'DNA: The Code of Life (SHA2017)' [3] gives an example of an IF-behaviour.
[1] https://en.wikipedia.org/wiki/KMT2D