RAD51

Homologous recombination repair (HRR) is the major DNA repair pathway directly modulating cellular sensitivity to DNA damaging agents and selected small molecules such as inhibitors of PARP or CDK. RAD51 is central to HRR, as it mediates pairing of homologous DNA sequences and strand invasion. The RAD51 gene is located on chromosome 15q14-15, a region of the human DNA that is frequently deleted in breast cancer and metastatic brain tumors.  It functions by forming nucleoprotein filaments in single-stranded DNA, mediating homologous pairing and strand exchange reactions between single and double stranded DNA during repair. RAD51 is central to HRR, as it mediates pairing of homologous DNA sequences and strand invasion. 
It functions by forming nucleoprotein filaments in single-stranded DNA, mediating homologous pairing and strand exchange reactions between single and double stranded DNA during repair.  RAD51 has been extensively studied as a marker of DNA repair capacity and as a surrogate marker for chemo- and radioresistance. RAD51 overexpression has been found in a variety of cancer cell lines and has been associated with resistance to DNA-damaging treatment. RAD51 gene polymorphisms have been shown to be associated with an increased risk of various cancer types.

References

1.Gachechiladze M,et al. Int J Cancer. 2017;141(7):1286–1294.