I was listening to Dr. Drew Pinsky the other night and he said that the tendency toward alcoholism is genetic. He also said that if one parent carries the gene, you have about a 50% chance of getting it, but if BOTH parents are alcoholics, you still have about a 50% chance of getting it. Can this be correct?
Why wouldn’t having TWO alcoholic parents put you at higher odds than having just ONE parent?
Thanks.
Does he state that there is a 50% chance of getting the gene or 50% chance of becoming an alcoholic?
This is just a WAG, but the chance of getting the gene itself may increase if both parents have it, but whether the child becomes alcohol dependant could depend on the child (or hopefully the adult version of that child). In other words, one may carry the gene but not necessarily be an alcoholic.
I believe he said there is about a 50% chance of getting the gene for alcoholism, regardless of whether one or both parents are alcoholics. It didn’t sound right to me.
And he frequently says that you can have the gene for alcoholic behavior, but it may show up in other ways, such as heavy pot smoking.
I shouldn’t post when I’m this deep over my head, but here are some ideas:
You only get half of each parent’s DNA. So the logic (cut two ways) works both ways: if one parent has it, half of your DNA comes from them, so that’s a 50% chance. If both parents have it, you only get half of each of their DNA, so that’s a 50% chance. I’m not saying it’s good logic, but that might be the thinking. Maybe what they really mean is up to a 50% chance?
WAG quotient of this answer … what else … 50%. 
There are few areas that I have come across with more bad science than alcoholism and drug addiction. Research is dominated by 12 steppers who happily cram every new bit of information into their theological disease model of addiction. One day they will say alcoholics process alcohol differently from others right from the first drink, the next day they are babbling about obsessive compulsive behavior. Treating the crap that comes from them as anything approaching actual knowledge is a mistake.
Genetic links have been demonstrated but they could be many, varied and have little to do with actual alcoholism. Left handed people are slightly more likely to be alcoholics for instance but it is far more likely that this is a social response than a biochemical relationship.
I assume that he is quoting studies that demonstrate 50% of children in the real world with one or both parents being alcoholics will end up with problems as well rather than theoretical genetic probabilities. I am sure that even he attributes this to a mix of genetic and social factors.
Well, let’s just talk about the gene. For some very dangerous mutations, showing the trait indicates the mutation is present on one chromosome; if it were on both chromosomes, you’d be dead. So your chance of inheriting the mutation from a single alcoholic parent is 50%. If both parents are alcoholics, you have a 25% chance of no mutation, a 50% chance of one copy (i.e., being an alcoholic), and a 25% chance of both chromosomes carrying the mutation, (i.e., being dead). This is one way that this statement could be true.
All that aside, however, this is a wildly inaccurate and irresponsible proclamation by Dr. Drew; what a surprise.
While it’s not surprising (and perhaps inevitable) that alcoholism has some genetic basis, there is no “gene for alcoholism.” this article goes a long way toward debunking this absurdly simplistic thinking (actually, it goes a bit too far in the other direction, but the arguments mostly hold water).