Related Experiment Video
Updated: Jul 1, 2025

Sex Stratified Neuronal Cultures to Study Ischemic Cell Death Pathways
Published on: December 9, 2013
Sex matters in preclinical research
1Program in Genetics and Genome Biology, The Hospital for Sick Children, Toronto, Ontario, M5G 0A4, Canada.
None:
International Women's Day 2024 has a theme of inclusion. As publishers of preclinical research, we aim to show how inclusion of females in research advances scientific rigor and improves treatment reliability. Sexual reproduction is key to all life across the plant and animal kingdoms. Biological sex takes many forms that are morphologically differentiated during development: stamens versus pistils in plants; color and plumage in birds; fallopian tubes versus vas deferens in mammals; and differences in size, for instance, males are smaller in the fruit fly Drosophila melanogaster. Physical differences may be obvious, but many traits may be more obscure, including hormonal, physiological and metabolic factors. These traits have a big influence on disease and responses to treatment. Thus, we call for improved inclusion, analysis and reporting of sex as a biological variable in preclinical animal modeling research.
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