Within the ARTD family, poly(ADP-ribose)polymerase (PARP)1 and PARP2 are activated by DNA single-strand breaks and are clinically validated targets in cancers with homologous recombination deficiency, such as breast cancer susceptibility genes 1/2 (BRCA1/2)-mutated breast cancer. This evidence concerns the gene PARP1 and breast carcinoma.