Science //

Of lab mice and men

Leigh Nicholson explores how a researchers’ pheromones might affect lab mice research.

The history of mouse use in scientific research may have potentially been ruined – at least according to a study by a team of researchers from McGill University, led by Jeffrey Mogil. Their study found that mice become stressed and scared if there are “male-typical” hormones present. This affects a lot of work because behavioural studies are severely impacted by the presence of stress in an animal. Mogil also points out that “pain is a proxy for stress, because stress can, to a large extent, numb pain.” Mice that were stressed were up to 35 per cent less sensitive to pain.

While the study showed that it was the presence of “male pheromones and hormones” causing the increased stress levels, there are some conditions to this. If stress-inducing factors were coupled with the presence of “female pheromones”, there was no effect as they cancelled each other out. Additionally, after a researcher hung around in the room for a longer than half an hour, there was no effect, suggesting the mice get used to the presence.

Deciding how to interpret and deal with these outcomes poses issues for researchers. For those unwilling to consider animal-free research, Mogil suggests getting researchers to hang around in the room before handling the animals. It is also suggested that researchers should start having to record their sex.

Suggesting that the solution is to force researchers to record their sex based on a hormone-production definition could be alienating for those whose androgens do not coincide with “normal production” as Mogil describes, which is very common and information one might not like to make public to a laboratory. Even just definitively defining the phenomena as “male-caused” creates room for unprofessional conduct. A quote by the head researcher, “the man who produced the least effect got some ribbing, because he was the least manly”, highlights the misunderstanding that has already been produced.

Sadaf Kalam, a researcher at the University of Sydney who works with mice, thinks that recording sex would not do much, saying that “that kind of protocol would not be enough of a control measure”. She explains that it would be near impossible to quantify how many people and other animals come within an influential range of the mouse in question. It wouldn’t be possible to remove these stresses from results.

It is unclear how the research community intends to proceed, the best idea probably being to ensure familiarity prior to animal handling. This, however, does nothing for research past.