Fig. 1.

HR and its sub-pathways. This figure is adapted from [59, 83, 84]. Multiple HR pathways through which DSB’s can be repaired give rise to either crossovers or non-crossover recombinants. SSA and MMEJ are typically mutagenic as they result in the loss of intervening DNA sequences at the break site. In SDSA, Rad51-mediated strand invasion is terminated before second end capture and prevents the formation of dHJ. In DSBR, after the Rad51 nucleofilament invades homologous DNA molecule, new DNA synthesis is primed from the 3′ end of the invading strand resulting in second end capture and subsequent dHJ formation. dHJ can either by resolved by the action of junction resolving enzymes or alternatively by the dissolution of the structure. The recombinant outcome of each subpathway, crossover or non- crossover, is indicated