Whats’ wrong with the Hutterities and Amish in the NEJM paper?

Following a recent discussion, I looked into more details of the Stein et al. 2016 NEJM paper. It claims that

Despite the similar genetic ancestries and lifestyles of Amish and Hutterite children, the prevalence of asthma and allergic sensitization was 4 and 6 times as low in the Amish.

The first sentence is correct. There is a similar genetic ancestry. Although that doesn’t mean anything as overlapping principal component plots are derived only by frequent SNP alleles that have no major disease impact.

The second sentence is also correct – and known for years BUT the implicit connection (“despite”) of both sentences is wrong. Propositional calculus.

If we go back to a widely cited paper on population genetics it’s rather clear, that there is big genetic difference between Amish and Hutterities. They have all kind of different disease.

We can safely add different asthma prevalences here which means that the whole paper of Stein et al. is collapsing now.

What about the reported mouse model of “experimental allergic asthma”? I wish such a model would exist. And I wish there is a magic dust mix.  And I wish, there would be reviewers who would have noticed that.