From what I recall being told it's not been proven to be genetic, however it tends to follow along families. But what is difficult to determine is the fact that most people don't realize they have this condition until they are tested and usually those only with stones have symptoms that take them to the doc in the first place -- so nobody really knows just how many have this disorder to begin with and are asymptomatic.
In my family my mom, dad, and brother all have had stones (me too) but I'm the only one who's had an IVP with contrast that confirmed the MSK diagnosis.
So far none of my children have the condition that we are aware of.
I was told when I was diagnosed that it was most likely genetic. If your concerned that them get an xray with contrast to see if the tubes in their kidneys are dialated