Drugmonkey recently re-upped one of his posts about the NIH requiring that experimental studies involve sex-difference analyses. That is, if you’re studying something in a mouse, you need to incorporate male and female mice. In principle, it’s a good idea, but in practice, it, if you’re lucky, doubles the cost of experiments.

To jump around a bit, a couple of months ago, concerns over replication and reproducibility flared up again like a bad case of hemorrhoids. While there are issues regarding technique and statistical analysis, some of the concerns about reproducibility–often by drug company representatives who were upset that model system biology doesn’t easily translate into blockbuster drugs–completely misunderstood what model systems in biology are about.

To jump back to the sex difference analyses, here’s what I noted last year:

But the other problem with the editorial is that it shows a misunderstanding of what model systems are. They are called model systems, not mimics for a reason. They exist to help us model (ahem) biological processes. Obviously, you don’t want to pick a completely inappropriate system–and for certain questions using only males (or males at all)–would be inappropriate. But they aren’t supposed to be perfect replicates of humans.

In other words, model systems are designed to help us elucidate biology, but they aren’t supposed to be ‘pre-clinical trial’ studies. Sometimes phenomena aren’t reproducible in other systems (including humans) because of those stupid fucking natural history facts. But men–and women–aren’t mice.