For example, 13% of breast cancers [11], 23% of advanced ovarian cancers [12], 6% of cervical cancers [13], and 4% of non–small-cell lung cancers [14] do not express BRCA1, a component of the HR machinery; missense mutations of the FANCA gene, whose protein product plays a key role in inter-strand crosslink repair, have been reported in 4-8% of acute myeloid leukemia (AML) patients [15, 16]; and inherited mutations in the DNA MMR genes are thought to be responsible for approximately 5% of the new cases of colorectal cancer diagnosed each year [17]. This evidence concerns the gene BRCA1 and acute myeloid leukemia.