BRCA1 and cancer: In a German study comparing BRCA1/BRCA2 MINAS and their single PV female relatives, Heidemann, Fischer [14] reported that BRCA1/BRCA2 MINAS were substantially younger at onset of first cancer (40.4 years) than their single heterozygous female relatives (51.9 years) and they also manifested more severe disease (1.4 vs. 0.6 manifestations per person).