BRCA1 and breast cancer: Several groups have demonstrated the usefulness of MLPA assay in the analysis of genomic rearrangements of BRCA1 and BRCA2. Hogervorst et al. using MLPA evidenced the presence of five distinct BRCA1 deletions/duplications in a series of 661 families with BC in which the screening of BRCA1 and BRCA2 point mutations was negative, suggesting that large genomic rearrangements could account for a large portion (about 27%) of all the BRCA1 mutations in families with hereditary BC [79].