For this purpose, genomic and gene expression profiles of basal-like BRCA1-mutated breast tumors (n = 27) were compared with basal-like familial BRCAX (non-BRCA1/2/CHEK2*1100delC) tumors (n = 14) in a familial cohort of 120 breast carcinomas.
Our data demonstrate that BRCAX hereditary breast tumours can be sub-classified into four previously unknown homogenous groups characterised by specific miRNA expression signatures and histopathological features.
This indicates that it might be possible to decrease the genetic heterogeneity among families in which BRCA1 and BRCA2 have been excluded with high certainty (BRCAx families) if distinct subgroups of BRCAx-related breast tumors could be identified.
Evaluation of linkage of breast cancer to the putative BRCA3 locus on chromosome 13q21 in 128 multiple case families from the Breast Cancer Linkage Consortium.