BRCA2, a conserved Rad51 mediator lost in ascomycetes.

BRCA2 is a central mediator of Rad51-dependent homologous recombination in humans. Its apparent absence from model yeasts long suggested that BRCA2 was restricted to higher eukaryotes. However, the identification of BRCA2 homologs across diverse fungal phyla reveals evolutionarily conserved BRCA2 function, with Ascomycota representing a notable exception.