RAD51C mutant oocytes (bottom), but not wild-type oocytes (top), show broken chromosomes (inset) and abnormal sister chromatid cohesion.
Homologous recombination during prophase I of meiosis ensures genetic variability in gamete genomes. Seven members of the RecA/RAD51 family are each essential for homologous recombination. All are thought to be important for early recombination events—such as forming the RAD51 foci that jump-start the process—but in vitro evidence suggested that one member, RAD51C, might also be important for the much later step of Holliday junction resolution.
Mutant female mice now further support this in vitro evidence. The team found that mice with too little RAD51C are frequently infertile. In infertile males, the majority of spermatocytes...
