Genetic predisposition increases the risk of familial breast cancer.
Recent studies indicate that genetic predisposition for familial breast
cancer can be ethnic-specific. However, current knowledge of genetic
predisposition for the disease is predominantly derived from Western
populations. Using this existing information as the sole reference to
judge the predisposition in non-Western populations is not adequate and
can potentially lead to misdiagnosis. Efforts are required to collect
genetic predisposition from non-Western populations. The Egyptian
population has high genetic variations in reflecting its divergent ethnic
origins, and incident rate of familial breast cancer in Egypt is also
higher than the rate in many other populations. Using whole exome
sequencing, we investigated genetic predisposition in five Egyptian
familial breast cancer families. No pathogenic variants in BRCA1, BRCA2
and other classical breast cancer-predisposition genes were present in
these five families. Comparison of the genetic variants with those in
Caucasian familial breast cancer showed that variants in the Egyptian
families were more variable and heterogeneous than the variants in
Caucasian families. Multiple damaging variants in genes of different
functional categories were identified either in a single family or shared
between families. Our study demonstrates that genetic predisposition in
Egyptian breast cancer families may differ from those in other disease
populations, and supports a comprehensive screening of local disease
families to determine the genetic predisposition in Egyptian familial
breast cancer. Egyptian_familial_breast_cancer_exome_variantsExome variants from five breast cancer families collected in Gharbiah disctrict, Egypt. DNA was extracted from blood cells using a FlexiGene DNA kit. Exome sequencing was done with TrueSeq Exome Enrichment Kit and on HiSeq2500, paired-end 2x150 at 100X coverage. Exome sequences were mapped to hg19 using Burrows-Wheeler Aligner and pre-processed with Picard Toolkit. Variants were called using Freebayes and annotated with ANNOVAR.EgyptianFBCExomeVariants.zip