A 7 Mb region within 11q13 may contain a high penetrance gene for breast cancer

Familial breast cancer represents up to 5% of all breast cancer cases. Recently, our group has performed a new SNP-based linkage study in 19 non-BRCA1/2 families. We found that a single family was linked to regions in two different chromosomes (11q13 and 14q21), and observed a non-parametric LOD score of 11.5 in both regions. In the present study, we ruled out any possible translocation between the chromosomes. We also used both a panel of STRs and an indirect approach based on HapMap data to narrow down these regions from 28 to 7 Mb in chromosome 11 and from 14.5 to 8.5 Mb in chromosome 14. We performed a mutational screening on candidate genes in 11q13 (NUMA1, FGF3, CCND1, RAD9A, RNF121, FADD and hsa-mir-192), and on FOXA1 in 14q21. Although we have not found any deleterious mutations in the coding region of these genes, data from STR markers confirm 11q13 as a candidate region to contain a breast cancer susceptibility gene.