I think it's likely genetic (though I'm no expert in the biology), however addiction is not a flaw. It's a dominant trait for a reason. Addiction helps people achieve amazing goals when directed at the right problem. The problem is when it gets directed towards negative things like alcohol, some drugs, or other destructive addictions (like hn or reddit ... partially joking). When directed at exercise, learning, building, writing, creating, or other positive passions, it can help addicts achieve what most non-addicts can't even fathom. It needs to be balanced though, which is sometimes the most difficult part, if it's even possible.

Applying addiction to work can be beneficial, but overdoing it (which is always the struggle) leads to workaholism. Even drugs and alcohol work the same way. A little can be amazing. A lot can lead to rehab or death. Or videogames. Programming. Technology. Music. Anything. Addictive behaviors can lead to a lot of good or a lot of bad. Great artists, musicians, programmers, designers, etc. Or living on the streets drinking, shooting up, or smoking crack/meth. Two sides of the same coin. It can be a thin line. It depends on the individual, their mentality, the support around them, and many other factors.

Only one thing's for sure. It's not a genetic flaw.