A model protocol evaluating the introduction of genetic assessment for women with a family history of breast cancer

Randomised controlled trials allow comparisons to be made between different models of service delivery, but have not been used in the field of clinical genetics. With the advent of clinical governance, the evidence provided by such trials will be increasingly important in informing and shaping clinical genetics practice. The TRACE project (Trial of genetic assessment in breast cancer) is a randomised controlled trial of genetic assessment for women who are at increased risk of breast cancer because of their family history. The absence of cancer genetics service provision in Wales before this study gave a window of opportunity in which this important trial could be conducted. The present paper describes how TRACE will provide crucial evidence regarding the psychosocial as well as resource implications of adding individualised genetic assessment, genetic counselling, and (where appropriate) gene testing to typical advice and surveillance from a hospital breast clinic. In addition, it is anticipated that TRACE will represent a model for future trials of service delivery in the increasing number of complex genetic disorders where evidence on the economic implications of screening and management is currently limited.     

Founder BRCA1 and BRCA2 mutations in French Canadian ovarian cancer cases unselected for family history

The breast cancer susceptibility genes, BRCA1 and BRCA2, differ in their contribution to ovarian cancer. Recently, founder mutations in each of these genes were identified in Canadian breast cancer and breast ovarian cancer families of French ancestry. We have examined the prevalence of the founder mutations in a series of 113 French Canadian women with ovarian cancer unselected for family history. Germline mutations were found in eight of 99 invasive carcinomas and in none of the 14 tumors of borderline malignancy. Five cases carried the BRCA1 C4446T mutation and two cases carried the BRCA2 8765delAG mutation which are the most common mutations that have been described in French Canadian breast cancer and breast ovarian cancer families. All of these cases reported a family history of at least one first-degree relative with breast cancer, diagnosed below age 60 years, or with ovarian cancer. The identification of founder BRCA1 and BRCA2 mutations in ovarian cancer cases unselected for family history can facilitate carrier detection when the expected yield of a comprehensive screen may be low.     

Younger birth cohort correlates with higher breast and ovarian cancer risk in European BRCA1 mutation carriers

Mutations in the BRCA1 gene result in an elevated risk of breast cancer (BC) and ovarian cancer (OC). However, risk estimates vary depending on the study population and statistical methodology used, and there are indications that the birth cohort and location of the mutation influence cancer risk. We investigated the risks for BC and OC associated with BRCA1 mutations in a young cohort of female mutation carriers who were identified by molecular genetic testing and belonged to a genetically heterogeneous Central European population. The study included 106 healthy and 158 affected carriers identified at an Austrian risk evaluation center. Risk estimation employed the product limit method. The log rank test was used to compare different strata. The risk of developing cancer to age 70 was found to be 85% for BC (95% CI 75-97%) and 53% for OC (95% CI 37-68%). Female mutation carriers born in 1958 or later were subject to a significantly higher risk of BC (P=0.005; 27% vs. 46% to age 40) and OC (P=0.006; 2% vs. 8% to age 40) than those born earlier. Mutations in exon 11 were associated with lower BC risk than mutations in exons 1-10 (P=0.008) and exons 12-24 (P=0.0006). OC risk was not influenced by mutation location (P=0.86). We conclude that female BRCA1 mutation carriers should be counseled about their cohort-dependent cancer risk. Further research into variables that affect cancer risk and are amenable to modification (e.g., lifestyle-related factors) should be considered a priority.     

The risk of breast cancer in BRCA1 and BRCA2 mutation carriers without a first‐degree relative with breast cancer

The objective of this study was to estimate the lifetime risk of breast cancer in women with a BRCA1 or BRCA2 mutation with and without at least 1 first‐degree relative with breast cancer. A total of 2835 women with a BRCA1 or BRCA2 mutation were followed. Age‐ and gene‐specific breast cancer rates were calculated. The relative risks of breast cancer for subjects with a family history of breast cancer, compared to no family history were calculated. The mean age at baseline was 41.1 years, and they were followed for a mean of 6.0 years. The estimated penetrance of breast cancer to age 80 years was 60.8% for BRCA1 and 63.1% for BRCA2. For all BRCA carriers, the penetrance of breast cancer to age 80 for those with no first‐degree relative with breast cancer was 60.4% and 63.3% for those with at least 1 first‐degree relative with breast cancer. The risk of breast cancer for BRCA carriers with no first‐degree relative with breast cancer is substantial, and as a result, clinical management for these women should be the same as those for women with an affected relative.     

Contribution of BRCA1 and BRCA2 mutations to inherited ovarian cancer

A total of 283 epithelial ovarian cancer families from the United Kingdom (UK) and the United States (US) were screened for coding sequence changes and large genomic alterations (rearrangements and deletions) in the BRCA1 and BRCA2 genes. Deleterious BRCA1 mutations were identified in 104 families (37%) and BRCA2 mutations in 25 families (9%). Of the 104 BRCA1 mutations, 12 were large genomic alterations; thus this type of change represented 12% of all BRCA1 mutations. Six families carried a previously described exon 13 duplication, known to be a UK founder mutation. The remaining six BRCA1 genomic alterations were previously unreported and comprised five deletions and an amplification of exon 15. One of the 25 BRCA2 mutations identified was a large genomic deletion of exons 19-20. The prevalence of BRCA1/2 mutations correlated with the extent of ovarian and breast cancer in families. Of 37 families containing more than two ovarian cancer cases and at least one breast cancer case with diagnosis at less than 60 years of age, 30 (81%) had a BRCA1/2 mutation. The mutation prevalence was appreciably less in families without breast cancer; mutations were found in only 38 out of 141 families (27%) containing two ovarian cancer cases only, and in 37 out of 59 families (63%) containing three or more ovarian cancer cases. These data indicate that BRCA1 and BRCA2 are the major susceptibility genes for ovarian cancer but that other susceptibility genes may exist. Finally, it is likely that these data will be of clinical importance for individuals in families with a history of epithelial ovarian cancer, in providing accurate estimates of their disease risks.     

BRCA1 5272-1G>A and BRCA2 5374delTATG are founder mutations of high relevance for genetic counselling in breast/ovarian cancer families of Spanish origin

Infante M, Durán M, Acedo A, Pérez-Cabornero L, Sanz DJ, García-González M, Beristain E, Esteban-Cardeñosa E, de la Hoya M, Teulé A, Vega A, Tejada M-I, Lastra E, Miner C, Velasco EA. BRCA1 5272-1G>A and BRCA2 5374delTATG are founder mutations of high relevance for genetic counselling in breast/ovarian cancer families of Spanish origin.
The distribution of BRCA1 and BRCA2 germ line mutations in breast/ovarian cancer families varies among different populations, which typically present a wide spectrum of unique mutations. Splicing mutation 5272-1G>A of BRCA1 and frameshift mutation 5374delTATG of BRCA2 are highly prevalent mutations in Castilla-León (Spain), accounting for 18.4% and 13.6% of BRCA1 and BRCA2 positive families, respectively. To test the presence of founder effects, 9 Spanish 5272-1G>A and 13 5374delTATG families were genotyped with polymorphic markers linked to BRCA1 or BRCA2 . All the 5272-1G>A families shared a common haplotype in eight markers (1.1 Mb region) and the mutation age was estimated in 15 generations (∼380 years). A conserved haplotype associated to 5374delTATG was observed in four markers (0.82 Mb). The mutation occurred approximately 48 generations ago (∼1200 years). Each mutation likely arose from a common ancestor that could be traced to a small area of Castilla-León and expanded to other Spanish regions. They can have a significant impact on the clinical management of asymptomatic carriers as well as on the genetic screening strategy to be followed in populations with Spanish ancestries.     

Frequency of three BRCA1 gene founder mutations in breast/ovarian cancer families from the Pomerania-Kujawy region of Poland

A group of 63 families from the Pomerania-Kujawy region were analyzed for three BRCA1 gene Polish founder mutations, 5382insC, 300T>G, and 4153delA, because of breast (BrCa) and/or ovarian cancer (OvCa) history. The analysis was carried out by multiplex polymerase chain reaction method. BRCA1 mutation was revealed in nine (14%) families: in three (33%) of hereditary BrCa and OvCa families, in three (8%) of hereditary BrCa families, and in three (21%) of hereditary OvCa families. According to risk criteria, it was revealed in 45% of high-risk families with more than three cancers, 13% of moderate-risk families with two cancers, and 8% of families with sporadic OvCa. In six families, the mutation was found in a proband with BrCa or OvCa and in three families, the mutation was found in a healthy proband, first-degree relative of a patient deceased of BrCa or OvCa. 5382insC frameshift mutation accounted for 67% and 300T>G missense mutation for 33% of all identified familial mutations. 4153delA frameshift mutation was not found in analyzed sample of families. 5382insC mutation was found in 9% and 300T>G in 5% of all investigated families, and in 27 and 18%, respectively, of high-risk families. This underlines the importance of applying strict inclusion criteria to analyze mutation frequency in hereditary BrCa/OvCa families.     

Evaluation of two different models to predict BRCA1 and BRCA2 mutations in a cohort of Danish hereditary breast and/or ovarian cancer families

To meet the increasing demand for BRCA1 and BRCA2 mutation analysis, a robust system for selecting families who have a higher chance of a mutation has become important. Several models have been developed to help predict which samples are more likely to be mutation positive than others. We have undertaken a complete BRCA1 and BRCA2 mutation analysis in 267 Danish families with high-risk family history. We found deleterious mutations in 28% (76) of the families, 68% (52) of those in BRCA1 and 32% (24) in BRCA2. We compared our results with two popular manual models developed to estimate the chance of a positive result. One is the recently published Manchester model and the other is the Frank 2 model updated by Myriad Genetic Laboratories, Inc. Neither of the models would have suggested screening all mutation-positive samples. The Manchester model would have suggested screening 124 of the families in the cohort, thereby detecting 54 of 76 mutations (sensitivity 71%; specificity 63%), whereas the Frank 2/Myriad model would have found 60 of 76 mutations by screening 169 samples if a 10% likelihood was adapted (sensitivity 79%; specificity 43%). The updated Manchester model suggested screening 172 families whereby 64 mutations would have been detected (sensitivity 84%; specificity 44%). We conclude that although both models would have reduced the number of samples screened significantly, up to 28% of the mutations would not have been found by applying these models to this Danish cohort of families. This raises the question whether models designed for specific populations can be used in a wider setting.     

Disclosure to the family of breast/ovarian cancer genetic test results: Patient's willingness and associated factors

Informed probands are key actors for disclosing genetic information to their relatives when a mutation has been identified in the family. The objectives were to study women's attitudes towards the family disclosure of positive breast cancer genetic testing results and to determine the predictive factors of the diffusion patterns observed. A national multi‐center cross‐sectional survey was carried out at five French cancer genetic clinics during a 1‐year period. Self‐administered questionnaires were completed after the consultation by 84.5% (398/471) of women attending breast cancer genetic clinics for the first time. Among the 383 respondents who had at least one living first‐degree relative to inform, 8.6% would inform none, 33.2% would inform at least one of them, and 58.2% would inform all of them. The sibship would be the most frequently informed blood relatives, sisters in 86.9% and brothers in 79% compared with mother in 71.4%, children in 70.4%, and father in 64.9%. Women of the family would be more frequently informed than men (P < 0.05). After multivariate adjustment, age, the fact to be affected by cancer, the number of daughters, and the emotional disturbance due to cancer in a close relationship were the main determinants (P < 0.05) of the diffusion patterns observed. The first step of the relatives' attendance to genetic counseling and the proband's willingness to disclose breast cancer genetic tests results was high in this study and was clearly dependent on the women's personal and emotional characteristics. Am. J. Med. Genet. 94:13–18, 2000. © 2000 Wiley‐Liss, Inc.     

Breast and ovarian cancer risk perception after prophylactic salpingo-oophorectomy due to an inherited mutation in the BRCA1 or BRCA2 gene

It is often recommended that women who carry a mutation in the BRCA1 or BRCA2 gene have their ovaries and fallopian tubes removed to reduce their risk of gynecologic cancer. The aim of this study was to evaluate women's perception of their risk of breast and ovarian cancer before and after prophylactic salpingo-oophorectomy. We surveyed 127 women who carry a BRCA1 or BRCA2 mutation and who underwent prophylactic salpingo-oophorectomy at the University Health Network, Toronto. Subjects were asked to estimate their risks of breast and ovarian cancer before and after surgery. Their perceived risks of cancers were then compared with published risks, based on their mutation status. BRCA1 carriers estimated their risk of breast cancer risk to be, on average, 69% before surgery and 41% after surgery. They estimated their risk of ovarian cancer to be 55% before surgery and 11% after surgery. BRCA2 carriers estimated their risk of breast cancer to be 69% prior to surgery and 45% after surgery and their perceived risk of ovarian cancer to be 43% before surgery and 8% after surgery. Compared with published risk figures, the perceived risk of ovarian cancer before prophylactic salpingo-oophorectomy was overestimated by 47% of BRCA1 mutation carriers and by 61% of BRCA2 mutation carriers. Most women who have undergone genetic counseling and subsequently choose prophylactic salpingo-oophorectomy accurately perceive their risk of breast cancer. However, in this study, many women overestimated their risk of ovarian cancer, particularly women who carry a BRCA2 mutation.     

Psychological functioning in African American women at an increased risk of hereditary breast and ovarian cancer

Despite attention to psychological issues during genetic counselling and testing for hereditary breast and ovarian cancer risk, limited information is available on cancer-specific distress among African American women being targeted for participation in counselling and testing. Therefore, the purpose of this study is to examine cancer-specific distress in African American women at an increased risk of hereditary breast and ovarian cancer and to identify factors having significant associations with distress in this population. Respondents were 141 African American women identified for participation in genetic counselling and testing for BRCA1/2 mutations. Overall, respondents reported moderate levels of cancer-specific distress. Younger age (coefficient=6.0, p=0.001), being unemployed (coefficient=-5.0, p=0.01), and having a personal history of cancer (coefficient=5.0, p=0.02) had significant associations with intrusion. Younger age was also associated significantly with greater avoidance (r=6.0, p=0.02). These results suggest that African American women aged 50 and younger, those who are unemployed and women with a personal history of breast or ovarian cancer may be the most vulnerable to experiencing elevated levels of distress during genetic counselling and testing. Greater attention to psychological issues, including concerns about cancer and cancer risks, may be needed during genetic counselling and testing for BRCA1/2 mutations with these women.     

In search of a familial cancer risk assessment tool

Approximately one in three individuals will be affected by cancer in their lifetime in the United States, and some are at elevated risk because of family history. Although assessment of family history of cancer and cancer risk is the standard of care, the current health-care system appears unable to meet this need. Because individuals are increasingly using the Internet, web-based cancer risk assessment tools (CRATs) may provide a way to meet this need. The purpose of this review was to evaluate the types of familial CRATs available on the Internet and their nature. The current review evaluated five CRATs identified through an Internet search based on (i) their ability to identify those at the highest risk of cancer (i.e. those with hereditary cancer syndromes), (ii) their strengths and limitations based on criteria adapted from Rich and colleagues (2004, 2005), (iii) their readability based on four readability calculations, and (iv) their quality based on criteria from Health on the Net. The general limitations of CRATs as a whole were also delineated, including concerns about availability to those who are poor and underserved and those who have lower levels of literacy. Recommendations for future tools include assessing risk for a greater number of diseases, using theoretically driven approaches to increase the likelihood that individuals will engage in appropriate health behaviors, and making a greater effort to reach diverse populations.     

Guidelines for a genetic risk based approach to advising women with a family history of breast cancer. UK Cancer Family Study Group (UKCFSG)

A family history of breast cancer has long been recognised as a significant risk factor for breast cancer. Quantifying that risk has been approached in publications and practically in a number of different ways. Increasingly regional genetics departments are called upon to help clarify guidelines for referral of women with a family history of breast cancer for genetic testing and to clarify breast cancer risk for women seeking early mammographic screening. This paper represents the current consensus guidelines from the UK Cancer Family Study Group and discusses some of the difficulties surrounding genetic risk estimation.     

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

Bogdanova NV, Antonenkova NN, Rogov YI, Karstens JH, Hillemanns P, Dörk T. 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.     

Lobulitis is a frequent finding in prophylactically removed breast tissue from women at hereditary high risk of breast cancer

The aim of this study was to investigate closely the nature of premalignant lesions that occur in prophylactically removed breast tissue from patients at hereditary high risk of breast cancer. Breast tissues obtained from 41 patients who underwent prophylactic mastectomy (pM) because of a hereditary high risk of breast cancer and control tissues from 82 age-matched healthy controls who underwent breast reduction surgery were screened for premalignant lesions. Premalignant and malignant lesions were more frequent (p = 0.0016) in pM samples (5/41) than in controls (1/82). Interestingly, lobulitis, defined as more than 100 lymphocytes and/or plasma cells per lobule in more than one section in morphologically normal lobules, was encountered in 21 of 41 (51%) pM patients, in contrast to only 8 of 82 (10%) controls (p < 0.0001). Preliminary observations indicate a predominance of T-cells in these infiltrates, in agreement with the already known frequent presence of lymphocytic infiltration in hereditary ductal in situ and infiltrating ductal/medullary carcinomas. This novel finding implies an immune reaction to an as yet unidentified antigen frequently present in women at hereditary high risk of breast cancer, possibly as part of an early carcinogenic event.     

The risk of contralateral breast cancer in daughters of women with and without breast cancer

We aimed to estimate the 15‐year and lifetime risks of contralateral breast cancer in breast cancer patients according to the age of diagnosis of the first cancer and the history of breast cancer in the mother. The risks of contralateral breast cancer were estimated for all 78,775 breast cancer patients in the Swedish Family‐Cancer Database (age at diagnosis of first breast cancer <70 years). The risk of experiencing a contralateral breast cancer within 15 years of diagnosis was 8.4% [95% confidence interval (CI): 8.1–8.7%] for women with an unaffected mother, was 12% (95%CI: 11–13%) for a woman with a mother with unilateral breast cancer and was 13% (95%CI: 9.5–17%) for women with a mother with bilateral breast cancer. In early‐onset diagnosed women (<50 years) with an unaffected mother, the risk of contralateral breast cancer until age 80 was 23% (95%CI: 20–26%) and for late‐onset (50–69 years) diagnosed women it was 17% (95%CI: 14–21%). In a woman with a mother with an early‐onset unilateral breast cancer, risk of contralateral breast cancer by age 80 was 35% (95%CI: 25–46%). Women with a mother with early‐onset bilateral breast cancer had 31% (95%CI: 12–67%) lifetime risk of contralateral breast cancer. The risk of contralateral breast cancer is higher for daughters of breast cancer patients than for daughters of women without breast cancer. Maternal cancer history and age at onset of first breast cancer in women should be taken into account when counseling breast cancer patients about their risk of contralateral breast cancer.     

Prospective comparison of family medical history with personal genome screening for risk assessment of common cancers

Family history-based risk assessment (FHRA) is a genetic tool for identifying those at risk of disease. Genome-wide association studies have shown that single nucleotide polymorphisms (SNP) are statistically associated with low- to moderate-level risks of diseases. There has been limited study of complementarity for these two assessment methods. We sought to compare cancer risk categorizations from FHRA and from Navigenics Personal Genome Screening (PGS). We compared FHRA with PGS for breast (22 females), prostate (22 males), and colon cancer (44 males and females) assessed by kappa (κ) statistic. We also assessed each participant's hereditary risk based on clinical criteria and/or gene-test results. Both FHRA and PGS placed 59%, 68% and 44% of participants into the same risk categories for breast, prostate, and colon cancer, respectively. Overall, however, there was little concordance in FHRA versus PGS for all three cancer risks (κ<0.2). FHRA assigned 22 with hereditary risk compared with PGS, which identified one as high risk (P<0.0001). We assessed nine with hereditary colorectal cancer risk, five with germline mutations, but none were classified as PGS high risk (P=0.0001). FHRA and PGS may be complementary tools for cancer risk assessment. However, evaluation of family history remains the standard to evaluate an individual's cancer risk until further research.     

Screening for large rearrangements of the BRCA1 gene in German breast or ovarian cancer families using semi-quantitative multiplex PCR method

Since the identification of the breast and ovarian cancer susceptibility genes BRCA1 and BRCA2, a large number of different germline mutations in both genes have been found by conventional PCR-based mutation detection methods. Complex germline rearrangements such as those reported in the BRCA1 gene are often not detectable by these standard diagnostic techniques. To detect large deletions or duplications encompassing one or more exons of the BRCA1 gene and in order to estimate the frequency of BRCA1 rearrangements in German breast or ovarian cancer families, a semi-quantitative multiplex PCR method was developed and applied to DNA samples of patients from families negatively tested for disease causing mutations in the BRCA1 and BRCA2 coding regions by direct sequencing. Out of 59 families analysed, one family was found to carry a rearrangement in the BRCA1 gene (duplication of exon 13). The results indicate that the semi-quantitative multiplex PCR method is useful for the detection of large rearrangements in the BRCA1 gene and therefore represents an additional valuable tool for mutation analysis of BRCA1 and BRCA2.     

Family history: A comprehensive genetic risk assessment method for the chronic conditions of adulthood

Targeting individuals with increased risk for common, chronic disease can improve the efficiency and efficacy of preventive efforts by improving the predictability of screening tests and participant compliance. Individuals with the greatest risk for these disorders are those with a genetic susceptibility. The purpose of this study was to determine the feasibility of using a single, comprehensive family history as a method for stratifying risk for many preventable, common genetic disorders. Family histories obtained in a prenatal diagnostic clinic were reviewed regarding cardiovascular diseases, diabetes and several cancers; 42.5% of individuals reported a family history for at least one of the disorders under study. Familial coronary artery disease was most commonly reported (29% of participants), followed by noninsulin-dependent diabetes (14%). Qualitative characterization of disease susceptibility was also accomplished using family history data. For example, occurrence of different cancers within pedigrees was suggestive of familial cancer syndromes, and clustering of noninsulin-dependent diabetes and cardiovascular disease suggested an insulin resistance syndrome. Depending on the specific disease, 5 to 15% of at-risk individuals had a moderately increased risk (2 to 5 times the population risk), and approximately 1 to 10% had a high risk (absolute risks approaching 50%). Family history reports of common, chronic disease are prevalent among the population at large, and collection and interpretation of comprehensive family history data is a feasible, initial method for risk stratification for many preventable, chronic conditions. These findings may have important implications for disease prevention and management. Am. J. Med. Genet. 71:315–324, 1997. © 1997 Wiley-Liss, Inc.     

Risk factors for detecting germline BRCA1 and BRCA2 founder mutations in Ashkenazi Jewish women with breast or ovarian cancer

We ascertained 184 Ashkenazi Jewish women with breast/ovarian cancer (171 breast and 13 ovarian cancers, two of the former also had ovarian cancer) in a self-referral study. They were tested for germline founder mutations in BRCA1 (185delAG, 5382insC, 188del11) and BRCA2 (6174delT). Personal/family histories were correlated with mutation status. Logistic regression was used to develop a model to predict those breast cancer cases likely to be germline BRCA1/BRCA2 mutation carriers in this population. The most important factors were age at diagnosis, personal/family history of ovarian cancer, or breast cancer diagnosed before 60 years in a first degree relative. A total of 15.8% of breast cancer cases, one of 13 ovarian cancer cases (7.7%), and both cases with ovarian and breast cancer carried one of the founder mutations. Age at diagnosis in carriers (44.6 years) was significantly lower than in non-carriers (52.1 years) (p<0.001), and was slightly lower in BRCA1 than BRCA2 carriers. Thirty three percent of carriers had no family history of breast or ovarian cancer in first or second degree relatives. Conversely, 12% of non-mutation carriers had strong family histories, with both a first and a second degree relative diagnosed with breast or ovarian cancer. The predicted values from the logistic model can be used to define criteria for identifying Ashkenazi Jewish women with breast cancer who are at high risk of carrying BRCA1 and BRCA2 mutations. The following criteria would identify those at approximately 10% risk: (1) breast cancer <50 years, (2) breast cancer <60 years with a first degree relative with breast cancer <60 years, or (3) breast cancer <70 years and a first or second degree relative with ovarian cancer.