In Vitro Toxicology Testing: It’s Time to Report the Sex of Cells

Abstract

In light of evidence taken from numerous fields indicating that males are routinely used more than females as test subjects,1-3 and the resulting poor outcomes of such practice,4,5 a conversation on balancing the sex of sample sets is not a new one. In a 2014 meta-analysis of nearly 300 studies, Prendergast and colleagues discovered that females have erroneously been considered more variable owing to their estrous cycle; instead, males were found to be more inconsistent under some experimental conditions.6 These results were subsequently confirmed by meta-analysis of microarray datasets.