@Article{oncologie.2020.014116,
AUTHOR = {Neslihan Duzkale, Nilnur Eyerci},
TITLE = {Double Heterozygosity in the <i>BRCA1/2</i> Genes in a Turkish Patient with  Bilateral Breast Cancer: A Case Report},
JOURNAL = {Oncologie},
VOLUME = {22},
YEAR = {2020},
NUMBER = {3},
PAGES = {161--166},
URL = {http://www.techscience.com/oncologie/v22n3/40581},
ISSN = {1765-2839},
ABSTRACT = {<i>BRCA1</i> and <i>BRCA2</i> tumor suppressor genes are responsible for a quarter 
of hereditary breast cancers. Double heterozygous (DH) pathogenic variant carrier
status in these genes is an extremely rare condition, especially in non-Askenazi 
individuals. We report a woman patient with bilateral breast cancer that carries DH 
disease-causing variants in <i>BRCA1/2</i> genes. The 45-year-old patient who was 
followed up with the diagnosis of metachronous bilateral breast cancer was 
diagnosed with cancer at the age of 39 and 43, respectively. <i>BRCA1/2</i> genes of the 
patient were evaluated using Next-Generation Sequencing. In the patient, the 
c.2800C>T (p.Gln934Ter) pathogenic variant in <i>BRCA1</i> and the c.9648+1G>C 
likely pathogenic variant in <i>BRCA2</i> were detected as DH. Segregation analysis in 
family members revealed that her two healthy siblings available for testing were 
heterozygous for either <i>BRCA1</i> or <i>BRCA2</i> variants, but her mother, who had a past 
diagnosis of ovarian cancer, was heterozygous for both <i>BRCA1</i> and <i>BRCA2</i>
variants. Germline double heterozygosity in inherited cancer is a rare condition, and 
as far as we know it is reported for the first time from patient population in Turkey.
Large-scale patient series are needed to determine the impact of double 
heterozygosity on diseases course, such as prognosis and treatment responses.},
DOI = {10.32604/oncologie.2020.014116}
}