Answer:
Mutations refer to the modifications in DNA that can influence the genetic variation as genetic variation monitors various genes in the populations of organisms, giving genetic material for the natural selection.
The BRC1 mutation seems to be more threatful due to the percentage of deaths being 18 in comparison to the percentage of deaths with BRC1 being 2.8 percent.
If a woman carries a mutated BRC1 gene, then the threat of woman dying of cancer becomes higher in comparison if she carries a BRC2 gene, however, this is applicable if she inherits a harmful mutation in the BRC1 genes.