A research team from the Center for Biomedical Research (CBMR), at the University of Algarve (UAlg), and Instituto Gulbenkian de Ciência (IGC), led by Rui Gonçalo Martinho (UAlg) and Paulo Navarro-Costa (UAlg and IGC) has identified the mechanism by which the fertilized egg balances out the differences between chromosomes inherited from the mother and the father. The study, now published in the scientific journal EMBO reports, may pave the way for future developments in the clinical management of infertile couples.