“ For decades, molecules with the potential to become drugs were tested on rodents of only one sex, in our case often male mice… Female models are more complex to understand since the hormonal cycle must be taken into account.” explains Elisabeth Traiffort, research director in the field of neuroscience at Inserm. Today, scientists are realizing that the biological variable of sex plays a major role. We hadn't imagined how different the results could be between males and females. "This observation is all the more fundamental as it implies not only adapting treatments, but also understanding the diseases themselves, some of which are known to develop quite differently depending on sex." Data from epidemiological and clinical studies show, for example, that men are more often diagnosed with early-onset neurodevelopmental disorders such as autism, but also with Parkinson's disease, for example. Conversely, Alzheimer's disease affects women more often. reports Alex DeCasien, a researcher at the American Institute of Mental Health, for Science and FutureWith her team, she decided to explore the impact of this biological factor.
Researchers analyzed gene expression in several brain areas in both humans and mice to understand how it varies according to sex. Their study reveals that more than 3,000 genes are not expressed in exactly the same way in men and women. Even more striking: 133 of these genes are expressed differently in men and women regardless of the brain area or cell type studied. And most of these genes are not located on the sex chromosomes, X and Y… "This provides clues about potential differences in healthy organisms, which forms the necessary basis for understanding pathological states," explains Alex DeCasien. The results of their work were published in the journal Science.
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