For example, the RING domain mutation BARD1R99E was initially reported to impair HR-driven DNA double-stranded break repair and confer sensitivity to genotoxic agents, including topoisomerase inhibitors, ionizing radiation, and Olaparib [55]; however, a separate study later found that re-expression of this mutant allele in BARD1-depleted cells restored resistance to PARPis, implying that the RING domain may be dispensable for HR proficiency or tumor suppression [56]. Here, BARD1 is linked to neoplasm.