Genetic tests DNA, genomic tests RNA as far as I know. JNF shared the more important items for PCa fathers and sons. I did the genetic testing for all of us and did not come up with anything unusual in the testing. A PCa father is the more important indicator for extra caution. Good luck with your boys, I will try again when mine hit 40.
https://www.genome.gov/about-genomics/fact-sheets/genetics-vs-genomics