“This discovery illustrates how development relies on finely tuned and precise orchestration of gene expression," said IRCM president and scientific director Jean-François Côté. 

"Understanding these mechanisms is essential to better grasp the origin of certain malformations." 

Beyond limb formation, these findings reveal a fundamental principle of development: cells must not only activate the right genes, but also remember which ones must remain switched off. This regulatory system helps prevent errors that could lead to congenital abnormalities.  

The next step in Kmita's research will be to identify the signals that guide the recruitment of these Polycomb complexes to the right genes at the right time—a key question for deepening scientists' understanding of embryonic development and its dysregulation.