In baby chickens still in the egg, turning off a gene called PPAR alpha doesn't stop a chemical (PFOA) from speeding up the heart. That means the chemical is affecting the heart through a different route.

What we've found so far does not support the idea that silencing PPAR alpha prevents PFOA-induced heart rate increase in chicken embryos. Our analysis of the available evidence suggests the opposite — that turning off the PPAR alpha gene does not stop the chemical PFOA from increasing heart rate in developing chickens. We reviewed one key assertion based on experimental data from chicken embryos [1]. This assertion indicates that even when PPAR alpha is silenced, PFOA still causes an increase in heart rate [1]. The finding implies that PFOA’s effect on heart rate likely happens through a different biological pathway, one that does not depend on PPAR alpha activity [1]. This single assertion is supported by six units of evidence, with no conflicting data reported. Our current analysis shows the evidence leans toward PPAR alpha not being a necessary part of the mechanism by which PFOA affects heart rate in these embryos. However, since we are working with limited data — only one assertion drawn from a narrow set of studies — we cannot rule out other possibilities or generalize beyond this specific context. We don’t yet know what other pathways might be involved, nor do we have data on whether similar effects occur in other species or under different conditions. As more evidence becomes available, our understanding may change. Practical takeaway: In chicken embryos, switching off the PPAR alpha gene doesn’t appear to protect against PFOA-related increases in heart rate, based on what we’ve seen so far.