BioMed Central Page 1 of 4 (page number not for citation purposes) Hereditary Cancer in Clinical Practice Open Access Case report Large family with both parents affected by distinct BRCA1 mutations: implications for genetic testing Anna P Sokolenko 1 , Dmitry A Voskresenskiy 1 , Aglaya G Iyevleva 1 , Elena M Bit-Sava 1 , Nadezhda I Gutkina 2 , Maxim S Anisimenko 2 , Nathalia Yu Sherina 1 , Nathalia V Mitiushkina 1 , Yulia M Ulibina 1 , Olga S Yatsuk 1 , Olga A Zaitseva 1 , Evgeny N Suspitsin 1 , Alexandr V Togo 1 , Valery A Pospelov 3 , Sergey P Kovalenko 2 , Vladimir F Semiglazov 1 and Evgeny N Imyanitov* 1 Address: 1 NN Petrov Institute of Oncology, St.-Petersburg, Russia, 2 Institute of Molecular Biology and Biophysics, Novosibirsk, Russia and 3 Institute of Cytology, St.-Petersburg, Russia Email: Anna P Sokolenko - annasokolenko@mail.ru; Dmitry A Voskresenskiy - dima_voskr@mail.ru; Aglaya G Iyevleva - aglayai@inbox.ru; Elena M Bit-Sava - bit-sava@mail.ru; Nadezhda I Gutkina - gutkinani@hotmail.com; Maxim S Anisimenko - max_anisimenko@mail.ru; Nathalia Yu Sherina - nata-lunna@mail.ru; Nathalia V Mitiushkina - nmmail@inbox.ru; Yulia M Ulibina - elhi@mail.ru; Olga S Yatsuk - olga- yatsuk@mail.ru; Olga A Zaitseva - zayats_vorchun@mail.ru; Evgeny N Suspitsin - suspitsin@hotmail.com; Alexandr V Togo - a_togo@mail.ru; Valery A Pospelov - pospelov_v@mail.ru; Sergey P Kovalenko - skoval@sibmail.ru; Vladimir F Semiglazov - contact@niioncologii.ru; Evgeny N Imyanitov* - evgeny@imyanitov.spb.ru * Corresponding author Abstract Although the probability of both parents being affected by BRCA1 mutations is not negligible, such families have not been systematically described in the literature. Here we present a large breast- ovarian cancer family, where 3 sisters and 1 half-sister inherited maternal BRCA1 5382insC mutation while the remaining 2 sisters carried paternal BRCA1 1629delC allele. No BRCA1 homozygous mutations has been detected, that is consistent with the data on lethality of BRCA1 knockout mice. This report exemplifies that the identification of a single cancer-predisposing mutation within the index patient may not be sufficient in some circumstances. Ideally, all family members affected by breast or ovarian tumor disease have to be subjected to the DNA testing, and failure to detect the mutation in any of them calls for the search of the second cancer- associated allele. Case presentation BRCA1 and BRCA2 mutations occur in approximately 0.2–1% healthy subjects, 5% non-selected breast cancer (BC) patients, 15% consecutive ovarian cancer (OC) cases, and 25% females with clinical features of hereditary breast-ovarian cancer (HBOC) syndrome [1-8]. Given low populational frequency and high penetrance of deleteri- ous BRCA1 and BRCA2 mutations, only one of the parent of the affected proband is usually suspected to contain this genetic lesion. Nevertheless, the probability of both parents being a carrier of BRCA1 or BRCA2 mutation is not negligible. If we consider random healthy couples, Published: 26 January 2009 Hereditary Cancer in Clinical Practice 2009, 7:2 doi:10.1186/1897-4287-7-2 Received: 9 September 2008 Accepted: 26 January 2009 This article is available from: http://www.hccpjournal.com/content/7/1/2 © 2009 Sokolenko et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0 ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.