TY - JOUR
T1 - Common genetic variants contribute to incomplete penetrance
T2 - evidence from cancer-free BRCA1 mutation carriers
AU - Downs, Bradley
AU - Sherman, Simon
AU - Cui, Jian
AU - Kim, Yeong C.
AU - Snyder, Carrie
AU - Christensen, Maria
AU - Luo, Jiangtao
AU - Lynch, Henry
AU - Wang, San Ming
N1 - Funding Information:
The authors thank Dr. Andrew Wilde (University of Toronto) for providing eGFP-anillin plasmid. This study was supported by an NIH grant CA180008 and three pilot grants from Fred & Pamela Buffett Cancer Center , University of Nebraska Medical Center (SMW), University of Macau Faculty of Health Sciences startup fund (SMW), American Cancer Society institutional grant (YCK), by revenue from Nebraska's excise tax on cigarettes awarded to Creighton Univeristy through the Nebraska Department of Health & Human Services (DHHS), the Charles F. and Mary C. Heider Chair in Cancer Research and Liz's Legacy fund through Kicks for a Cure (HL). The funders have no roles in study design, data collection and analysis, decision to publish or preparation of the article. The authors thank Ms. Khyati Chandratre for article editing.
Funding Information:
The authors thank Dr. Andrew Wilde (University of Toronto) for providing eGFP-anillin plasmid. This study was supported by an NIH grant CA180008 and three pilot grants from Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center (SMW), University of Macau Faculty of Health Sciences startup fund (SMW), American Cancer Society institutional grant (YCK), by revenue from Nebraska's excise tax on cigarettes awarded to Creighton Univeristy through the Nebraska Department of Health & Human Services (DHHS), the Charles F. and Mary C. Heider Chair in Cancer Research and Liz's Legacy fund through Kicks for a Cure (HL). The funders have no roles in study design, data collection and analysis, decision to publish or preparation of the article. The authors thank Ms. Khyati Chandratre for article editing.
Publisher Copyright:
© 2018 Elsevier Ltd
PY - 2019/1
Y1 - 2019/1
N2 - Purpose: The presence of pathogenic germline mutation in BRCA1 gene is considered as the most penetrant genetic predisposition for breast cancer. However, a portion of BRCA1 mutation carriers never develops breast cancer throughout their lifetime. This phenomenon is called incomplete penetrance. Genetic factor is proposed to contribute to this phenomenon, but the details regarding the genetic factor remain elusive. BRCA1 mutations were inherited from the ancestors of the mutation carrier families during human evolution, and their presence is a consistent threat to the survival of the mutation carrier population. In the present study, we hypothesize that evolution could positively select genetic components in the mutation carrier population to suppress the oncogenesis imposed by the predisposition. Experimental design: To test our hypothesis, we used whole exome sequencing to compare germline variation of all genes in pairs of breast cancer–unaffected and breast cancer–affected BRCA1 mutation carriers, each pair was from the same family carrying the same BRCA1 mutation. Results: We identified a group of ‘beneficial’ variants enriched in the breast cancer–unaffected carrier group. These were the common variants in human population distributed in multiple genes involved in multiple functionally important pathways. We found a single-nucleotide polymorphism, rs3735400 located in ANLN gene, which plays an essential role in controlling cytokinesis and is often found to be overexpressed in cancer. The carriers of this variant had lower cumulative risk of developing breast cancer; overexpression of the variant-containing ANLN decreased ANLN nuclear localization suppressed expression of the variant-containing ANLN, and decreased the cellular proliferation respectively. Conclusion: Our findings support our hypothesis that common genetic variants can be evolutionarily selected in BRCA1 mutation carrier population to counterpart the oncogenic effects imposed by mutation predisposition in BRCA1, contributing to the incomplete penetrance.
AB - Purpose: The presence of pathogenic germline mutation in BRCA1 gene is considered as the most penetrant genetic predisposition for breast cancer. However, a portion of BRCA1 mutation carriers never develops breast cancer throughout their lifetime. This phenomenon is called incomplete penetrance. Genetic factor is proposed to contribute to this phenomenon, but the details regarding the genetic factor remain elusive. BRCA1 mutations were inherited from the ancestors of the mutation carrier families during human evolution, and their presence is a consistent threat to the survival of the mutation carrier population. In the present study, we hypothesize that evolution could positively select genetic components in the mutation carrier population to suppress the oncogenesis imposed by the predisposition. Experimental design: To test our hypothesis, we used whole exome sequencing to compare germline variation of all genes in pairs of breast cancer–unaffected and breast cancer–affected BRCA1 mutation carriers, each pair was from the same family carrying the same BRCA1 mutation. Results: We identified a group of ‘beneficial’ variants enriched in the breast cancer–unaffected carrier group. These were the common variants in human population distributed in multiple genes involved in multiple functionally important pathways. We found a single-nucleotide polymorphism, rs3735400 located in ANLN gene, which plays an essential role in controlling cytokinesis and is often found to be overexpressed in cancer. The carriers of this variant had lower cumulative risk of developing breast cancer; overexpression of the variant-containing ANLN decreased ANLN nuclear localization suppressed expression of the variant-containing ANLN, and decreased the cellular proliferation respectively. Conclusion: Our findings support our hypothesis that common genetic variants can be evolutionarily selected in BRCA1 mutation carrier population to counterpart the oncogenic effects imposed by mutation predisposition in BRCA1, contributing to the incomplete penetrance.
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U2 - 10.1016/j.ejca.2018.10.022
DO - 10.1016/j.ejca.2018.10.022
M3 - Article
C2 - 30551077
AN - SCOPUS:85058022571
VL - 107
SP - 68
EP - 78
JO - European Journal of Cancer
JF - European Journal of Cancer
SN - 0959-8049
ER -