Do You Have the 'Internet-Addiction Gene'?

"German scientists find 'internet-addiction gene'," said a headline on a German news site last week. Another site reported that scientists have "nailed down the gene responsible for internet addiction."

Is it true? No, but its falseness is interesting for what it says both about the nature of our addictions and about how scientific researchers sometimes help journalists sensationalize research.

Here's what the German scientists found: People who reported heavy dependence on the internet--including feelings of unhappiness when denied access to it--were more likely to have a certain gene than comparable people who weren't so internet-dependent.

One thing that would be nice to know, before we decide how excited to get about this result, is: How much more likely? Do 90 percent of internet addicts have this gene whereas only 15 percent of non-addicts have it? Or is the difference much less dramatic than that?

So far as I can tell, not one of the journalists who wrote about this--not even the one whose story appeared on the estimable Washington Post's web site--found the answer to that question before writing about this research. And, in their defense, the answer wasn't trivially easy to find. The German scientists didn't cite the numbers in the publically available abstract of their paper. And if you want to read the paper itself, you have to hand over $49 to the Journal of Addiction Medicine.

Well, in a rash moment, I actually plunked down the money. And it turns out that the numbers are underwhelming: 27 percent of the people identified as internet addicts had the gene, whereas 17 percent of non-addicts had it. In other words, the "gene responsible for internet addiction" isn't found in most people who are addicted to the internet! And the chances that a non-addict will have the gene are, relatively speaking, pretty high--63 percent as high as the chances that an addict will have it.

It would be nice if scientists whose data are prone to sensationalizing would work to keep things in perspective--by, say, revealing their actual, unspectacular quantitative findings in their publically available abstracts, or by making sure those numbers are included in their press releases. In this case the scientist did roughly the opposite. The lead author, Christian Montag, declared in the press release that he and his colleagues had uncovered a genetic link that plays an "essential" role in internet addiction.

Montag also said we can now conclude that "internet addiction is not a figment of our imagination." (This became the WashingtonPost.com headline: "Internet addiction is real, German researchers say." To the Post's credit, this piece described the genetic contribution to internet addiction in more guarded terms than other pieces.)

What's Montag talking about? Is he saying that something we call an addiction isn't really an addiction unless the likelihood of acquiring it is correlated with genetic differences? So if it turned out that, in terms of genetic predisposition, we're all equally susceptible to heroin addiction, then heroin addiction wouldn't be an addiction? That doesn't seem to make any sense.

I'm not saying these findings are wholly insignificant. It's interesting, for example, that the gene in question is also associated with nicotine addiction. And it could be that that's why Montag thinks these findings establish the reality of internet addiction--because they link internet addiction to a gene associated with a "real" addiction, a chemical addiction.

But when you think through why a gene statistically associated with "internet addiction" might also be involved in nicotine addiction, you realize how unsurprising that is, and you come away more convinced than ever that these research findings have been hyped by both journalists and scientists. I'll explain exactly what I mean in a follow-up post later this week. Meanwhile, I'll give you what will be one take-home lesson from that post: We all have genes that could be called "internet addiction genes." Lots of them.