It is certainly true that a.) Native Americans have a much higher rate of alcoholism than other U.S. populations; and b.) Native Americans metabolize alcohol differently due to genetics. But, suprisingly b does not account for a, at least in the writing I've seen on the subject.
From: http://alcohol.addictionblog.org/is-native-american-alcoholism-genetic/ - this is just a blog, but I have seen similar findings discussed in multiple sources.
"The main current theories for alcoholism among American Indians focus on alcohol metabolism to try to explain why alcohol dependence rates are so high among the population. Some researchers have thought that Native Americans are predisposed to alcoholism because of differences in the way they metabolize alcohol. More specifically, researchers think that alcohol metabolism may affect the regulation of alcohol intake, because interference with production or elimination of the alcohol metabolite acetaldehyde has behavioral effects. And while studies of families, twins, and adoptees support a genetic predisposition to alcoholism may confirm this, the exact genetic code has yet to be cracked.
What researchers have found is that alcohol is broken down and eliminated differently in Native Americans than in other populations. So far, studies have found a variant of the ALDH1 enzyme that is encoded by the ALDH1A1*2 allele and a variant of the ADH1B enzyme that is encoded by the ADH1B*3 allele. However, the genes that have been identified in Native Americans are associated with a protective effect and do not explain the high rates of alcoholism in the tribes investigated.
It is a puzzlement :-)
In any case, for the beer suit the bottom line remains the same - adults, of whatever predisposition, need to take responsibility for their own behavior. I am an alcoholic, but I took responsibility for myself and stopped drinking in 2007, and haven't had a drink since. (And there are people with far longer abstinences.) If I start to drink again, it's nobody's fault but my own. If Native Americans drink, it's their responsibility.
Thanks!