5382insC Mutation Research Articles

High frequency and allele‐specific differences of BRCA1 founder mutations in breast cancer and ovarian cancer patients from Belarus

Breast cancer and ovarian cancer are common malignancies in Belarus accounting for about 3500 and 800 new cases per year, respectively. For breast cancer, the rates and age of onset appear to vary significantly in regions differentially affected by the Chernobyl accident. We assessed the frequency and distribution of three BRCA1 founder mutations 5382insC, 4153delA and Cys61Gly in two hospital-based series of 1945 unselected breast cancer patients and of 201 unselected ovarian cancer patients from Belarus as well as in 1019 healthy control females from the same population. Any of these mutations were identified in 4.4% of the breast cancer patients, 26.4% of the ovarian cancer patients and 0.5% of the controls. In the breast cancer patients, BRCA1 mutations were strongly associated with earlier age at diagnosis, with oestrogen receptor (ER) negative tumours and with a first-degree family history of breast cancer, although only 35% of the identified BRCA1 mutation carriers had such a family history. There were no marked differences in the regional distribution of BRCA1 mutations, so that the significant differences in age at diagnosis and family history of breast cancer patients from areas afflicted by the Chernobyl accident could not be explained by BRCA1. We next observed a higher impact and a shifted mutational spectrum of BRCA1 in the series of Byelorussian ovarian cancer patients where the three founder mutations accounted for 26.4% (53/201). While the Cys61Gly mutation appeared underrepresented in ovarian cancer as compared with breast cancer cases from the same population (p = 0.01), the 4153delA mutation made a higher contribution to ovarian cancer than to breast cancer (p < 0.01). BRCA1 mutations were significantly enriched among ovarian cancer cases with a first-degree family history of breast or ovarian cancer, whereas the median age at ovarian cancer diagnosis was not different between mutation carriers and non-carriers. Taken together, these results identify three BRCA1 founder mutations as key components of inherited breast and ovarian cancer susceptibility in Belarus and might have implications for cancer prevention, treatment and genetic counselling in this population.

Identification of point mutations and large rearrangements in the BRCA1 gene in 667 Turkish unselected ovarian cancer patients

Objective The aim of this study was to evaluate the prevalence and spectrum of a known founder mutation, 5382insC and large genomic rearrangements (LGRs) in BRCA1 in ovarian cancer patients in Turkey. The additional aim was to determine the genetic testing strategy in Turkish breast/ovarian cancer family. Methods Six hundred and sixty-seven ovarian cancer patients from five large geographical regions in Turkey, 61 of which had family history of breast/ovarian cancer, were tested for the mutation 5382insC by mutagenically separated polymerase chain reaction and direct sequencing of the entire coding sequence and the splicing sites. Additionally, multiplex ligation-dependent probe amplification (MLPA) was performed for large mutational scanning of BRCA1 gene in unselected ovarian cancer. Results In this study, BRCA1 point mutations were observed in 1% of all patients and 9.8% of familial cases: 5382insC, unique novel missense variant-G1748S and unclassified splice site variant IVS20 + 5A > T. 5382insC was observed in two patients. However, G1748S, previously unreported, was found in four patients and thus led to the conclusion that this mutation may be unique to Turkey. A splice site variant, IVS20 + 5A > T, was detected in three patients, with two of them including G1748S and IVS20 + 5A > T, together. Using MLPA, six different distinct LGRs in BRCA1 were observed: the deletion of E1A-1B-2, E11, E17-19, E18 and E18-19 and duplication of E5-9. The prevalence of LGRs in this study was 40.9% among patients with family history. The deletion of E1A-1B-2 was the common mutation, and patients with this deletion were referred to us from four different geographical regions in Turkey. Therefore, it was hypothesized that this deletion covering E1-2 is common in Turkey. Conclusion LGRs in BRCA1 were strongly associated with positive family history among the Turkish population. On the basis of these findings, it can be recommended that a low-cost screening for LGRs in BRCA1 may be the first-line mutation detection method in families with strong breast/ovarian cancer history in Turkey.

BRCA1 mutations in women with familial or early-onset breast cancer and BRCA2 mutations in familial cancer in Estonia

BackgroundThe aim of this study was to identify BRCA1 and BRCA2 mutations in the Estonian population. We analyzed genetic data and questionnaire from 64 early-onset (< 45 y) breast cancer patients, 47 familial cases (patients with breast or ovarian cancer and a case of these cancers in the family), and 33 predictive cases (patients without breast or ovarian cancer, with a family history of such diseases) from Estonia for mutations in the BRCA1 gene. A sub-set of familial cases and predictive cases were also analyzed for mutations in the BRCA2 gene.MethodsFor mutation detection, we used the Polymerase Chain Reaction-Single Stranded Conformation Polymorphism Heteroduplex Analysis (PCR-SSCP-HD), followed by direct DNA sequencing.ResultsWe identified three clinically important mutations in the BRCA1 gene, including seven occurrences of the c.5382insC mutation, three of c.4154delA, and one instance of c.3881_3882delGA. We also detected six polymorphisms: c.2430T>C, c.3232A>G, c.4158A>G, c.4427T>C, c.4956A>G, and c.5002T>C. Four sequence alterations were detected in introns: c.560+64delT, c.560+ [36-38delCTT, 52-63del12], c.666-58delT, and c.5396+60insGTATTCCACTCC. In the BRCA2 gene, two clinically important mutations were found: c.9610C>T and c.6631delTTAAATG. Additionally, two alterations (c.7049G>T and c.7069+80delTTAG) with unknown clinical significance were detected.ConclusionsIn our dataset, the overall frequency of clinically important BRCA1 mutations in early-onset patients, familial cases, and predictive testing was 7.6% (144 cases, 11 mutation carriers). Pathogenic mutations were identified in 4 of the 64 early-onset breast cancer cases (6.3%). In familial cases, clinically important mutations in the BRCA1 gene were found in 6 of the 47 individuals analyzed (12.8%). In predictive cases, 1 clinically important mutation was detected in 33 individuals studied (3%). The occurrence of clinically important mutations in BRCA2 in familial cases of breast cancer was 2 of the 16 individuals analyzed (12.5%).

Detection of BRCA1and BRCA2 mutation for Breast Cancer in Sample of Iraqi Women above 40 Years

Breast cancer is the commonest cancer affecting women worldwide. Different studies have dealt with the etiological factors of that cancer aiming to find a way for early diagnosis and satisfactory therapy. The present study clarified the relationship between genetic polymorphisms of BRCA1 &amp; BRCA2 genes and some etiological risk factors among breast cancer patients in Iraq. This investigation was carried out on 25 patients (all were females) who were diagnosed as breast cancer patients attended AL-Kadhemya Teaching Hospital in Baghdad and 10 apparently healthy women were used as a control, all women (patients and control) aged above 40 years. The Wizard Promega kit was used for DNA isolation from breast patients and normal individuals. By this method suitable quantities of DNA approximately (50 µl) with purity ranged from (1.7-1.9) were obtained from 100-200µg of fresh biopsy which had been taken from women breast patients. The extracted DNA was successfully used in amplification of BRCA1 &amp; BRCA2 genes by PCR and some mutation were detected. The outcome of genetic analysis indicated that the percentage of 185delAG mutation was 16 (4 patients) whereas, the percentage of 5382insC mutation was 32 (8patients) in BRCA1 gene and the third mutation 6174delT in BRCA2 present in 3 patients only (12%). The study demonstrated that the frequency of BRCA1 mutation (48%) was higher than BRCA2 (12%) in this sample of Iraqi women with breast cancer.

ESTIMATION OF GENETIC PREDISPOSITION TO BREAST CANCER BY TESTING OF MOST FREQUENT MUTATIONS OF BRCA1 AND BRCA2 GENES IN GROUP OF PATIENTS FROM GOMEL REGION OF BELARUS

The work that has been carried out describes for the first time the hereditary caused breast cancer cases in Gomel region of Belarus, having defined a spectrum and frequencies of the most significant genetic factors underlying the given pathology. After the molecular-genetic testing of 667 primary breast cancer cases it was shown that out of eight BRCA1/2 gene mutations that are widely spread in Eastern Europe there are only five ones in Gomel region of Belarus with various frequencies - 185delAG, 300T&gt;G, 4153delA, 5382insC and 6174delT. The 2274insA, 3819del5 and 3875del4 mutations were not found in the studied group. The 5382insC mutation was found to be the predominant one, which has made 80 % of all the detected mutations. Total mutation frequency in nonselective sampling taking into consideration the standardized indicators of age structure has made 7,9 %. It was found out, that family anamnesis is the most significant criterion from the point of view of probability estimation of BRCA1/2 mutations in genotype. In the united subgroup of patients with any of the basic signs of family cancer and their combinations, the share of mutations has made 24,4 %.

Detection of the 5382insC mutation in the human BRCA1 gene with fluorescent labeled oligonucleotides

Analysis of genetic predisposition to cancer provides valuable information for early cancer detection or even prevention. The 5382insC insertion in the BRCA1 gene is the most frequent mutation among those associated with high breast cancer risk in women of East European origin. A method for 5382insC detection with fluorescent labeled allele-specific oligonucleotides in the Duplex Scorpion format has been developed. The method can be used under real-time PCR conditions as well as under the conditions of end-point fluorescence measurement following regular PCR. The adequacy of the method was demonstrated in the study of the 5382insC mutation frequency in breast cancer patients. A total of 564 genomic DNA samples from breast cancer patients were screened. Eleven patients (1.95%) were found to carry the mutation under consideration in the heterozygous state. The 5382insC allele frequency in the breast cancer patient group was 0.0098. The method is appropriate in clinical practice to detect individuals at high breast cancer risk, as well as in large-scale population studies.

Mutation scanning of exon 20 of the BRCA1 gene by high-resolution melting curve analysis

Objectives 5382insC frameshift mutation along with 5331G>A (G1738R) missense mutation, both found in exon 20 of the BRCA1 gene, are relatively frequent among the Greek breast and ovarian cancer population (46%). Our goal was to develop a novel, reliable and rapid genotyping/scanning method for mutation detection of the exon 20 of the BRCA1 gene, using high-resolution melting curve analysis. Design and methods The developed methodology was based on real-time PCR and high-resolution melting curve analysis in the presence of LCGreen I dye. Two amplicons on the exon 20 of BRCA1 gene were designed (157 bp and 100 bp), one flanking the exon's boundaries, and one embracing the 5382insC mutation. Our methodology was first optimized and validated by using genomic DNA samples with the 5382insC and 5331G>A (G1738R) mutations and wild-type. In total, the developed methodology was applied on 90 peripheral blood and 127 formalin-fixed paraffin-embedded breast tissue samples. Results Sensitivity studies with gDNA isolated from peripheral blood showed that mutated DNA could be reliably detected in the presence of wild-type DNA at 5% and 0.5% ratio with the larger and the smaller amplicon, respectively. By using the developed methodology we successfully identified 5382insC, 5331G>A and 5370C>T (R1751X) mutations, in genomic DNA isolated from peripheral blood samples and 5382insC mutation in two breast tumors, as verified by DNA sequencing. Conclusions The combination of real-time PCR and high-resolution melting curve analysis provides a cost-efficient, simple and rapid approach to successfully scan exon 20 of BRCA1 gene for these clinically important and frequent mutations.

Associations of high-grade prostate cancer with BRCA1 and BRCA2 founder mutations.

Protein-truncating mutations in BRCA1 and in particular BRCA2 genes have been associated with prostate cancer. However, there is still uncertainty about the magnitude of association particularly with Gleason score, and family history of prostate, breast, and ovary cancers. To further examine associations between three founder mutations located in BRCA1 (185delAG, 5382insC) or BRCA2 (6174delT) genes and prostate cancer, we conducted a study of 979 prostate cancer cases and 1,251 controls among Ashkenazi Jewish men. Detailed information was obtained on prostate cancer pathology, age at diagnosis, and family history of all cancers. Odds ratios (OR) and 95% confidence intervals (CIs) were estimated using logistic regression models. Prostate cancer risk was increased (OR, 1.9; 95% CI 0.9-4.1) for BRCA2 mutation carriers but not for BRCA1 mutation carriers. BRCA2 mutation carriers had an OR of 3.2 (95% CI, 1.4-7.3) for Gleason score of 7 to 10, but no association was observed for Gleason score of < 7. Carriers of BRCA1-185delAG mutation also had an OR of 3.5 (95% CI, 1.2-10.3) for Gleason score of > or =7 tumors; however, the association of either BRCA1-185delAG or 5382insC mutation was not statistically significant. Associations between founder mutations and prostate cancer were stronger in men with no first-degree family history of breast and/or ovarian cancers but were unaffected by family history of prostate cancer. These results indicate that the BRCA2 founder mutation confers a 3-fold elevated risk of high-grade prostate cancer. Although BRCA1 mutations were not associated with prostate cancer, the BRCA1-185delAG was associated with high Gleason score tumors. These findings should be carefully considered in genetic counseling and/or evaluating therapeutic options.

Large family with both parents affected by distinct BRCA1 mutations: implications for genetic testing

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.

Prevalence of BRCA1 and BRCA2 genes mutations in a sample of families with high risk of breast and ovarian cancer in Brazil.

Abstract Abstract #6020 Introduction: Of all malignant neoplasia among women, breast cancer has the highest incidence rate in Brazil. The objective of the present study was to ascertain the frequency of genetic modifications in a high risk population for breast and ovarian cancer from different regions of Brazil. Methods: An exploratory, descriptive study was carried out on the prevalence of the BRCA1 and BRCA2 mutations in case series of high risk families to breast and/or ovarian cancer. Following the respective heredogram construction, a sample of blood was taken and DNA extraction was performed to all index cases. The protein truncation test (PTT) was used to screen for truncated mutations in exon 11 of the BRCA1 gene and in exons 10 and 11 of the BRCA2 gene. Results: Of the 612 individuals submitted to genetic testing, 21 (3.4%), 19 women and 2 men, had mutations in the BRCA1 or BRCA2 genes. BRCA1 mutations consisted of ins6kb, 5382insC, 2156delGinsCC, 185delAG, C1201G, C3522T and 3450del4 mutations, while BRCA2 mutations were 5878del10, 5036delA and 4232insA. Conclusion: The prevalence of germline mutations in the BRCA1 and BRCA2 genes found in the present study was lower than reported by other studies in Brazil. The inclusion of individuals with medium risk may have contributed towards the lower observed prevalence. Nevertheless, individuals with a high probability of carrying mutations should be advised with respect to the possibility of undergoing genetic testing, and of the risks, benefits and limitations of these tests. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6020.

Functional variant of the tumor suppressor klotho: a novel risk modifier for breast cancer among BRCA1/2 carriers.

Abstract Abstract #1041 Background: The aging suppressor klotho is a transmembrane protein which is expressed in the kidneys, brain and hormone-responsive tissues and can be shed and act as a circulating hormone. The klotho gene is located on chromosome 13q12, about 700,000 base-pairs upstream to the BRCA2 gene. Klotho is a potent inhibitor of the insulin-like growth factor (IGF)-1 signaling pathway. We have recently found high klotho expression in normal breast tissue and low expression in breast cancer. Over-expression of klotho suppressed growth and inhibited the IGF-1 pathway in breast cancer cells. These data suggest klotho as a tumor suppressor gene in breast cancer. A single nucleotide polymorphism (SNP) in the klotho gene results in an amino acid substitution, F325V, which is associated with altered activity of klotho and reduced lifespan in human. As BRCA mutations may be associated with increased expression of IGF-1 and its receptor in breast cancer, we hypothesized that klotho functional variant may be associated with increased cancer risk among BRCA mutations carriers.&amp;#x2028; Material and Methods: The presence of F325V variant was evaluated using exon-specific polymerase chain reaction followed by restriction enzyme analysis, in a cohort of 784 Israeli women consisting of 236 non-BRCA mutations carriers (healthy: 109, breast cancer: 94, ovarian cancer: 33), 340 BRCA1 185delAG and 5382insC mutation carriers (healthy: 138, breast cancer: 142, ovarian cancer: 60) and 208 BRCA2 6174delT carriers (healthy: 75, breast cancer: 106, ovarian cancer: 27).&amp;#x2028; Results: Similar distribution of the F325V variant was noted in non-carriers and BRCA1 carriers (FF, wild-type 78%; FV, heterozygous 19%; VV, recessive 3%). However, F352V was over-represented among BRCA2 carriers: FF 25%, FV 50% and VV 25%. Analysis of additional SNPs indicated linkage disequilibrium between FV and BRCA2 6174delT mutation. Yet, among BRCA2 carriers, FF was significantly more frequent among healthy individuals compared to cancer patients (18% vs. 6% respectively, p=0.02). Surprisingly, among BRCA1 carriers FV status was associated with significantly younger age at breast cancer presentation compared to FF status (38±1.8 vs. 46±1.6 years respectively, p&amp;lt;0.001). Association between FV status and age at ovarian cancer presentation among BRCA1 carriers could not be assessed due to small sample size. No association was noted between the klotho functional variant and age at presentation among non-carriers of BRCA mutations.&amp;#x2028; Discussion: Taken together, these data suggest klotho F352V functional variant as a novel risk modifier among BRCA mutation carriers but not among non-carriers. As BRCA1/2 mutations can enhance and wild type klotho inhibits the activity of the IGF-1 signaling in cancer, it is possible that the presence of the less active variant of klotho attenuates this balance, thus leading to enhanced activation of the pathway. If validated by additional studies, the presence of the F352V klotho variant may serve as a predictor of cancer risk among BRCA mutation carriers and may also be a novel target for cancer therapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1041.

Hereditary Breast Cancer and Hereditary Non-Polyposis Colorectal Cancer: Description of Two Families, as the Examples of Classical Hereditary Predisposition to Cancers

The diagnosis of hereditary cancer syndromes is basing mainly on pedigree analysis and if possible on molecular studies. We present 2 families which were diagnosed with hereditary cancer syndromes. Family I – breast cancer syndrome; 9 breast cancer cases were diagnosed in women between 25 and 45-year-of-age from 4 generations. The brcA1 5382insC mutation was found in family members. Family II – hereditary nonpolyposis colon cancer; altogether 17 cancers in 12 persons from 6 generations were diagnosed. The c.256 C>T mutation in mlH1 gene was found in family members. Thus, written family genetic counselings were prepared for both families, including detail information concerning cancer risk for carriers and non-carriers of critical mutation in given family. In conclusion it was stated that an effective prevention dedicated to patients at high, hereditary risk of cancer could be achieved by early diagnosis and thus by highly targeted surveillance and managements.

Screening 101 renal cancers for somatic mutations in 3,726 genes

The frequencies of four mutations in the BRCA1 gene (185delAG, T300G, 4153delA, and 5382insC) were estimated in the Russian population. The mutations were analyzed in 7920 DNA samples obtained from randomly selected Novosibirsk citizens and 570 samples from breast cancer patients at Siberian hospitals. The mutations were detected by allele-specific real-time PCR. The mutation analysis was performed with pooled DNA samples to reduce the cost of the study. The 5382insC mutation was found in 20 of 7920 (0.25%) population DNA samples and in 14 of 570 (2.46%) breast cancer samples; the T300G mutation was detected in 4 population samples (0.05%) and in 2 breast cancer samples (0.35%); the 185delAG or 4153delA mutations were not identified in any of the 7920 samples and were detected in 1 (0.18%) breast cancer case each.

Founder effect of the BRCA1 5382insC mutation in Brazilian patients with hereditary breast ovary cancer syndrome

The 5382insC mutation in BRCA1 is a frequently reported mutation, being very prevalent in Central and Eastern Europe. This mutation was recurrently reported in Brazil and one case was reported Portugal, but not in Spain and other South-American countries,. We analyzed the haplotypic profile of seven Brazilian carriers of 5382insC to characterize a possible founder effect. The analyses indicated that mutation carriers shared an identical haplotype. The absence of this mutation in Spain, other South American countries, and sub-Saharan populations, as well as the patients’ own ancestry, point to a significant Central or Eastern European contribution to the present genetic background of Brazilian population, different from the population structuring of remaining South American countries.

Prevalence of BRCA1 and BRCA2 founder mutations in Brazilian hereditary breast and ovarian cancer families

22108 Background: Breast cancer (BC) is a significant health care problem in Brazil and only a few studies have been conducted to verify the contribution of founder mutations in BRCA genes to the occurrence of these tumors, especially in high risk families. Two recent studies in the State of Rio de Janeiro described a higher than expected prevalence of the BRCA founder mutations usually seen in individuals of Ashkenazi Jewish origin in non-Jewish breast cancer-affected women. The largest of these studies, conducted by Gomes et al., described a prevalence of 2.3% of the BRCA1 mutation 5382insC these patients were unselected for family history of the disease. Methods: Patients affected with breast cancer or other tumors of the HBOC spectrum, whose familiy histories fulfilled the ASCO criteria for HBOC and/or who had a prior probability of carryng a BRCA mutation ≥30% (using the Myriad prevalence tables and/or the Penn II model) were recruited from high risk genetics clinics in the cities of Rio de Janeiro and São Paulo. All patients denied Ashkenazi Jewish ancestry. Mutation detection was performed by PCR-amplification of the regions of interest in BRCA1 and BRCA2 followed by DNA sequencing. All mutations were confirmed in an independent sample. Results: A total of 145 unrelated patients were tested. None of them carried the 185delAG or 6174delT mutations in BRCA1 and BRCA2, respectively. Five (5) patients carried the BRCA1 mutation 5382insC in the germline, resulting in a prevalence of 3.44% for this mutation in the HBOC families studied. Conclusions: Testing for the three common BRCA founder mutations in non-Ashkenazi Brazilian women is probably not justified, especially not for the 185delAG and 6174delT mutations; the BRCA1 mutation 5382insC however, was relatively frequent. Additional haplotyping studies will be necessary to determine if these mutants share a common haplotype with those identified in individuals of Ashkenazi origin. No significant financial relationships to disclose.

Application of multiplex PCR with histopathologic features for detection of familial breast cancer in formalin-fixed, paraffin-embedded histological specimens

Breast cancer is the most common malignancy among females in the world. Age and familial history are the major risk factors for the development of this disease in Iran. Mutations of BRCA1 and BRCA2 genes are associated with a greatly increased risk for development of familial breast cancer. Frequency of BRCA mutations was identified in familial breast cancers (FBC) and non-familial breast cancers (NFBC) by molecular genetics, morphological and Immunohistochemical methods. Thirty forth formalin-fixed, paraffin-embedded breast tissue tumors were analyzed from 16 patients with FBC and 18 patients with NFBC. Three 5382insC mutations detected by multiplex PCR in 16 familial breast cancers. Immunohistochemical method was used to detect estrogen receptor (ER) and progesterona receptor (PR) and TP53. Comparison of ER, PR and TP53 exhibited high difference (P < 0.0001) in familial breast cancers and non-familial breast cancers. Our results demonstrated that 5382insC mutation, ER, PR, TP53, mitotic activity, polymorphism, necrosis and tubules can serve as the major risk factors for the development of FBC.

BRCA1 mutations and prostate cancer in Poland

Evidence to date that BRCA1 mutation carriers are at an increased risk of prostate cancer is mixed - both positive and negative studies have been published. To establish whether or not inherited variation in BRCA1 influences prostate cancer risk we genotyped 1793 men with prostate cancer in Poland and 4570 controls for three founder mutations (C61G, 4153delA and 5382insC). A BRCA1 mutation was present in 0.45% of the cases and 0.48% of the controls (odds ratio=0.9; P=1.0). The odds ratios varied substantially by mutation. The 5382insC mutation is the most common of the three founder mutations. It was detected only in one case (0.06%), whereas it was seen in 0.37% of controls (P=0.06). In contrast, the 4153delA was more common in prostate cancer cases (0.22%) than in controls (0.04%) (odds ratio=5.1; 95% confidence interval: 0.9-27.9; P=0.1). The C61G mutation was also found in excess in cases (0.17%) compared with controls (0.07%) (odds ratio=2.6; 95% confidence interval: 0.5-12.7; P=0.5). Eight men with prostate cancer carried a mutation. Only one of these carried the 5382insC mutation, compared with 17 of 22 individuals with mutations in the control population (P=0.003). These data suggest that the 5382insC mutation is unlikely to be pathogenic for prostate cancer in the Polish population. The presence of one of the other alleles was associated with an increased risk for prostate cancer (odds ratio=3.6; 95% confidence interval: 1.1-11.3; P=0.045); in particular for familial prostate cancer (odds ratio=12; 95% confidence interval: 2.9-51; P=0.0004). We consider that the risk of prostate cancer in BRCA1 carriers varies with the position of the mutation.

Asymmetric real-time PCR detection of BRCA1 5382insC mutation by melting curve analysis in the LightCycler

Background 5382insC BRCA1 frameshift mutation is a common founder mutation for many populations worldwide and a high-risk allele for the development of hereditary breast and/or ovarian cancer. Our goal was to develop a novel, reliable and rapid method for its detection. Methods We developed an asymmetric real-time PCR method with hybridization probes in the LightCycler. Genotyping was performed by melting curve analysis. Results and conclusions The developed method was in concordance with reference methods when tested in 85 peripheral blood and 107 tumor DNA samples from Greek breast and/or ovarian cancer patients. The described method proved to be simple, cost-effective, easy to perform and rapid enough for routine use as a screening method in high-risk families and especially in the Greek, Slavic and Jewish populations where 5382insC mutation is the most common BRCA1 mutation.

High incidence of mutations in BRCA1 and BRCA2 genes in ovarian cancer

The incidence of mutations in the BRCA1 and BRCA2 genes in the studied sampling of 74 patients with ovarian cancer was 19%. The incidence of mutations in the Russian sampling of patients, formed without consideration for the family history, is one of the highest in European countries. Retrospective analysis showed that 9% patients carrying mutation had no family history of ovarian or breast cancer. The majority of mutations (86%) were detected in BRCA1 gene, where 5382insC mutation predominated (58%). These data suggest the possibility and advisability of screening for mutations in the BRCA1/2 genes in patients with ovarian cancer, particularly because this population includes patients without family history of ovarian and/or breast cancer.

Founder mutations in early-onset, familial and bilateral breast cancer patients from Russia

Previous studies indicate that founder mutations may play a noticeable role in breast cancer (BC) predisposition in Russia. Here we performed a systematic analysis of eight recurrent mutations in 302 BC cases (St.-Petersburg, Russia), which were selected due to the presence of clinical indicators of hereditary disease (bilaterality and/or early onset (< or =40 years) and/or family history). BC-associated alleles were revealed in 46 (15.2%) women. BRCA1 5382insC mutation was detected in 29 (9.6%) patients, CHEK2 1100delC in 9 (3.0%), BRCA1 4153delA in 3 (1.0%), CHEK2 IVS2+1G>A in 2 (0.7%), and BRCA1 185delAG, BRCA2 6174delT and NBS1 657del5 in 1 (0.3%) patient each. No cases with BRCA1 300T>G (C61G) mutation was identified. The obtained data suggest that a significant fraction of hereditary BC cases in Russia can be diagnosed using only a limited number of simple PCR tests.