This Article Abstract Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Malacrida, S. Articles by Montagna, M. Search for Related Content PubMed PubMed Citation Articles by Malacrida, S. Articles by Montagna, M. Related Articles Related Editorial Related Correspondence

BRCA1 p.Val1688del Is a Deleterious Mutation That Recurs in Breast and Ovarian Cancer Families From Northeast Italy

Sandro Malacrida, Simona Agata, Monia Callegaro, Cinzia Casella, Daniela Barana, Maria C. Scaini, Siranoush Manoukian, Cristina Oliani, Paolo Radice, Monica Barile, Chiara Menin, Emma D'Andrea, Marco Montagna

From the Department of Oncology and Surgical Sciences, Oncology Section; Istituto Oncologico Veneto - IRCCS, Padua; U.O.A. ULSS 5 Ovest Vicentino, Vinicenza; Fondazione IRCCS Istituto Nazionale Tumori; FIRC Institute of Molecular Oncology Foundation; and the European Institute of Oncology, Milan, Italy

Corresponding author: Marco Montagna, PhD, Istituto Oncologico Veneto, UOC Immunologia e Diagnostica Molecolare Oncologica, via Gattamelata, 64; I-35128 Padova, Italy; e-mail: montagna{at}unipd.it

	ABSTRACT

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
Purpose: A growing number of sequence changes of unknown clinical significance are being identified in the BRCA1 gene. However, these variants cannot be used for identification and surveillance of at-risk individuals unless their pathogenic role can be demonstrated. The frequency of these variants makes research on this subject a relevant topic in the field of predisposition to breast and ovarian cancers. Herein, we investigate the pathogenicity of the BRCA1 p.Val1688del (c.5181_5183delGTT) variant, which recurs in our population.

Patients and Methods: Recent studies have drawn attention to different strategies that, if considered singly, do not usually provide sufficient power to firmly state for or against causality, thus forcing to a re-evaluation of the literature on each specific variant. To increase the power of our study, we used a recently described strategy that integrates data from multiple independent evidences. By this approach, we analyzed data from the comprehensive study of 12 breast/ovarian cancer families carrying p.Val1688del.

Results: We succeeded in integrating five independent evidences of disease causality including segregation, tumor pathology, and evolutionary and epidemiologic data. Under this model, we obtained a final score of 349,000:1 in favor of disease causality. This result largely matches established cutoffs, and thus is readily translatable into a clear clinical message.

Conclusion: We show that p.Val1688del is a pathogenic mutation deriving from a common founder. Notably, this study alone increases by 15% the number of BRCA1-positive families in our patients’ cohort, thus substantially contributing to explain many of the families wherein prediction of a BRCA1 mutation contrasted with the absence of a molecular recognizable defect.

	INTRODUCTION

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
Since the cloning of the BRCA1 gene,¹ an exceedingly high number of sequence variants have been identified during the molecular screening of high-risk breast cancer families. With the exception of mutations that cause a premature termination of the protein or a few missense mutations affecting the cysteine amino acid residues of the amino-terminal "ring finger" domain, a large number of these variants remain unclassifiable because they have no obvious effect on the coded protein. In the absence of conclusive data on their pathogenicity, such variants, commonly referred to as unclassified variants (UVs), cannot be used to identify predisposed individuals in high-risk families, thus limiting the clinical benefits of the genetic test.

More than 8,500 entries are catalogued in the Breast Cancer Information Core (BIC; http://research.nhgri.nih.gov/bic/) as BRCA1 or BRCA2 alleles of unknown clinical relevance. The vast majority of these are single amino acid substitutions, and a few cause in-frame deletions of one to three amino acids. Considering a typical sample cohort, consisting of high-risk families with various degrees of cancer family history, these types of changes might be identified in as many as 10% to 20% of the families.² As such, the attribution of a pathogenic role to even a small part of UVs might result in a relevant increase in the number of informative families.

For this reason, more and more studies are addressing the issue of UV pathogenicity using different experimental designs. The genetics-based methods vary from the classical genetic-epidemiologic studies to those evaluating co-segregation of the variant with disease and/or co-occurrence in trans with known deleterious mutations.^3,4 Another series of approaches focuses on the specific amino acid change, and includes analysis of interspecies conservation, severity of the amino acid change,^5,6 and effect on specific protein functions (functional tests), the latter being limited to the ring and BRCT domains of the BRCA1 gene.^7,8 Finally, pathologic features of the tumors occurring in the carriers of the variants such as loss of the wild-type allele, as well as histopathologic parameters defining the so-called BRCAness signature have also been used in a few studies as a tool for pathogenicity prediction.^2,9

Here, we used an integrated approach based on independent evidences to unveil the pathogenic significance of a sequence variant that recurs in the Northern Italian breast and breast/ovarian cancer families.

	PATIENTS AND METHODS

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
Family Recruitment
Nine of the families carrying p.Val1688del were identified through the Padua Hereditary Breast/Ovarian Cancer Center of the Istituto Oncologico Veneto (Padova, Italy), and three were from the Istituto Nazionale Tumori and Istituto Oncologico Europeo based in Milan. Family inclusion criteria were based on published operational criteria.¹⁰ Blood samples were obtained from each proband or family member after informed consent as to the aims of the research project. The study was performed in accordance with the principles embodied in the Declaration of Helsinki and was approved by the Oncology Centre Ethical and Technical-Scientific Committees.

Sequence Analysis and Databases
Mutation nomenclature follows the general recommendations of the Human Genome Variation Society: cDNA and protein numbering were based on GenBank entries U14680 (numbering according to BIC database) and AAA73985, respectively.

Potential cryptic splice sites and exonic splicing enhancers were investigated by means of BDGP Splice Site Prediction (http://www.fruitfly.org/seq_tools/splice.html), NetGene2 (http://www.cbs.dtu.dk/services/NetGene2/), and ESEfinder (http://rulai.cshl.edu/cgi-bin/tools/ESE3/esefinder.cgi).

Co-Segregation
DNA extracted from peripheral-blood leukocytes or lymphoblastoid cell lines using conventional phenolchloroform procedures, was polymerase chain reaction (PCR) amplified using primers 17F 5'-GGGTTTCTCTTGGTTTCTTT-3' and 17R 5'-TCGCCTCATGTGGTTTTA-3'. PCR products were sequenced on an ABI-PRISM-3130XL genetic analyzer (Applied Biosystems, Foster City, CA) using the BigDye Terminator Cycle Sequencing Reaction Kit (Applied Biosystems), according to the manufacturer's protocol. Analysis of co-segregation was performed with the Linkage package (http://capella.uni-kiel.de/gmc2006/linkage/user.pdf) assuming a genetic model with an allele frequency of 0.0001 and penetrance of 0.75 in carriers of the variant.

Co-Occurrence
Coexistence of the variant with known BRCA1 pathogenic mutations was evaluated on the results of the BRCA1 and BRCA2 screening in a cohort of more than 600 high-risk breast/ovarian cancer families. Briefly, this cohort was screened for point mutations by denaturing high-performance liquid chromatography (DHPLC) and for genomic rearrangements by multiplex ligation-dependant probe amplification (MLPA) as previously described.¹¹ Odds of causality for this analysis were derived by the multifactorial likelihood ratio model proposed by Goldgar¹² using an overall frequency of deleterious BRCA1 mutations of 10% obtained in our cohort of patients.

Tumor Loss of Heterozygosity and Histopathology
DNA was extracted from the paraffin-embedded breast tumor sample of patient B853, from family #14, using the QiAmp DNA mini Kit (Qiagen, Hilden, Germany), and from the ovarian cancer cells of proband B105 (family #78) with standard phenolchloroform procedures. Loss of heterozygosity (LOH) analysis was performed by PCR amplification of the fragment containing p.Val1688del, followed by DHPLC separation using the multifragment application.

Likelihood ratios were calculated using the probability distribution for the three observed LOH results previously described.⁹ For histopathologic data, we used odds of causation based on estrogen-receptor status in combination with histologic grade as described by Chenevix-Trench et al.²

Haplotype Analysis
Genotyping of the microsatellites D17S855, D17S1322, D17S1323, and D17S1327 was achieved by independently amplifying each marker using FAM-labeled primers followed by visualization of the PCR products by capillary electrophoresis. The allelic phase was determined by typing parents or tumoral tissues carrying the somatic loss of one allele as in the case of patient B105 from family #78.

Conservation
The constrain position likelihood (con-LR) was calculated using parameters previously defined on the basis of a 12-sequence alignment that contains full-length BRCA1 sequences from eight placental mammals plus M. domestica, G. gallus, X. laevis, and T. nigroviridis.⁶

Statistical Analysis
The multifactorial model described by Goldgar et al¹² and subsequently improved^2,9 was used to determine the contribution to odds of causation of independent factors as the probability of the observed data given that the variant is a deleterious mutation, against the probability of the observed data under the hypothesis that the variant is neutral, using previously established cutoffs of 1,000:1 and 100:1 to classify variants as deleterious or neutral, respectively.

	RESULTS

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
We first identified the deletion of BRCA1 valine 1688 approximately 10 years ago.¹³ Although, at that time, p.Val1688del was demonstrated in two affected members of a single family, the deletion of one valine over the 1,864 amino acid residues of the BRCA1 protein created uncertainty as to the pathogenic relevance of the variant. We have now completed the screening of the entire coding sequence of BRCA1 and BRCA2 genes of more than 600 breast and breast/ovarian cancer families and identified this variant in eight additional affected index cases. As a first step, p.Val1688del was excluded from the analysis of 200 geographically matched healthy controls, thus ruling out the possibility that this deletion might represent a common polymorphic variant. To increase the power of the study, three additional, independent families were added to our samples, thus reaching a total number of 12 independent families carrying the p.Val1688del. Although the pedigrees included, on average three to four generations and all families were from the Veneto Region (including the three families ascertained in different North Italian centers), we were unable to connect any of the pedigrees. However, the presence of a common ancestor who carried the p.Val1688del was confirmed by analysis of four microsatellite markers spanning the BRCA1 locus. Sharing of a common haplotype was observed among all 12 families (data not shown).

As shown in Table 1 all families displayed features reminiscent of a BRCA1 gene defect. In particular, clinical parameters usually employed to predict the probability of identifying a BRCA1 mutation were all overrepresented in this sample set. Among them were bilaterality of breast cancer (four of 12 probands), occurrence of breast and ovarian cancer in the same patient (three probands), and early age at cancer diagnosis, with mean values of 39.4 and 50.3 for breast and ovarian cancer, respectively. Consistently, predictions of BRCA1/2 mutations by the Italian version of the BRCAPRO software¹⁴ ranged from 0.5 to 1.0 with only one exception falling outside of this range (Table 1). Despite these predictions, mutations with an already established clinical significance were not identified in either BRCA1 or BRCA2 genes, nor were mutations in four additional carriers of the p.Val1688del identified by Myriad Genetics, as reported at the BIC. These data lend support to the pathogenicity of the p.Val1688del and gave a score of 1.85:1 in favor of causality using a model based on the co-occurrence with deleterious mutations.⁶ Of course, as this method was established on the supposed lethality of BRCA1 homozygotes, it proves much more powerful in showing odds in favor of neutrality rather than causality.

View larger version (16K): [in this window] [in a new window] [PowerPoint Slide for Teaching]   Fig 1. Pedigrees of two families carrying the p.Val1688del. The presence (M) or absence (W) of p.Val1688del is indicated under each tested individual. Numbers refer to current age and age at diagnosis for healthy and affected subjects, respectively. Probands are marked by arrows.

Most of the BRCA1 mutations result from short deletions or insertions of a few nucleotides within short repeated sequences; similarly, deletion of the GTT causing p.Val1688del occurs within a trinucleotide repeat. Apparently, the deletion of these three nucleotides does not create any cryptic splice site, nor modify potential exonic splicing enhancer sequences as confirmed by software analysis (BDGP Splice Site Prediction, NetGene2, ESEfinder), thus likely excluding a possible interference with splicing processes.

We first named the sequence variant indicating the most 3' GTT according to consensus guidelines on mutation nomenclature. In functional terms, however, deletion of Val1687 or Val1688 is a synonymous event. Both these amino acid residues fall within a well-conserved region of the BRCT domain. Valine 1688 is substituted by an isoleucine in half of the 12 BRCA1 orthologs from different species used in the Grantham analysis,⁶ whereas valine 1687 is one of the 130 invariant positions through the 12 species considered, thus suggesting that this residue is under strong functional constrain. Therefore, considering the constrain position likelihood as a predictor of variant pathogenicity, two scores of 27 and 2.7 were obtained for Val1687 and Val1688, respectively. To remain as conservative as possible to reduce the risk of false-positive results, the lowest score was subsequently used for integration with odds obtained from independent evidences.

Considering all of the results described herein, we derived a combined odd of causality on the assumption that all sources of data taken into consideration are independent of each other, following the approach proposed by Goldgar.¹² Under this model, the likelihood ratios obtained were multiplied to obtain a final score of 349,000:1 (1.85 x 661 x 3.8 x 27.8 x 2.7), thus definitely exceeding the minimal ratio of 1,000:1 for classification as pathogenic.

	DISCUSSION

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
Detection of BRCA1 and BRCA2 point mutations in families at high risk for breast/ovarian cancer has largely disappointed expectations of identifying a molecular defect in most of the families linked to either gene. The reason of this inconsistency can be ascribed, at least in part, to genetic defects affecting the same genes but escaping detection or recognition as pathogenic mutations. For instance, we have previously shown that, in the Italian population, some of the noninformative patients are actually carriers of genomic rearrangements involving BRCA1^11,16,17 and, to a lesser extent, BRCA2 genes.¹⁸ Another relevant fraction of families can likely be attributed to unrecognized mutations that, because of their nonobvious effect on the coded protein, cannot be used for identification of predisposed individuals within families. Notably, variants of this type are currently identified in a fraction of families similar to the one with a recognized BRCA1 or BRCA2 defect. Therefore, discriminating true pathogenic from benign variants is currently becoming a major issue in the understanding of the genetic basis of many hereditary breast and ovarian cancers.

Of the 527 different BRCA1 variants classified at the BIC as variations of unpredictable clinical relevance, and accounting for 2,818 entries, the vast majority are missense substitutions that occur throughout the entire coding sequence of the gene. Twenty-three different in-frame deletions are likewise included among UVs because they affect one to three amino acids on a total of 1,864 residues.

In this study, we investigated the pathogenic relevance of the variant p.Val1688del, which occurs in 1.5% of our families and was identified in a total of 12 families from Northern Italy. Haplotype analysis confirmed that this variant has a common founder whose descendants live in a geographical region located among the Italian provinces of Padua, Vicenza, and Rovigo. Notably, none of the p.Val1688del carriers were from any of these cities.

Using a number of independent approaches, we show that p.Val1688del is a pathogenic mutation affecting the BRCA1 function, likely by altering the functionality of the BRCT domain. Indeed, Val1688 and Val1687, both of which can be considered the target of the deletion, lie in a highly conserved region of the BRCT, and are integral parts of the third beta sheet of the first BRCT. In this regard, a recent study identified a putative binding site located on the opposite face from the well-characterized phosphopeptide binding cleft. Interestingly, valine 1687 was identified as part of one of the two hydrogen bonding networks formed by residues of this groove.¹⁹ Therefore, deletion of a valine in these positions is very likely to profoundly perturb the architecture of the BRCT domain. Accordingly, one of the first studies based on the intrinsic transactivation activity of BRCT domain reported an impaired function for mutants carrying the p.Val1688del unable to transactivate transcription of different target genes when fused to GAL4 or LexA DNA-binding domains in yeast and mammalian-based assays.²⁰

The clinical data of the 12 families analyzed in this study are consistent with a highly penetrant effect of p.Val1688del. Specifically, ages at disease diagnosis in all genotyped affected carriers were not statistically different from those calculated from carriers of pathogenic mutations.²¹ Similarly, while displaying interfamily variation, the ratio of breast to ovarian cancers of 2.8:1 is consistent with previously described genotype-phenotype correlation models suggesting that mutations in the 3' third of the gene are associated with a lower proportion of ovarian cancer.²² Significantly, all of these models were largely based on truncating mutations, thus indirectly suggesting that the effect of p.Val1688del is consistent with the alteration of the remaining part of the protein. Mean age at diagnosis, as well as proportion of breast/ovarian cancers, did not differ significantly when considering either all affected patients, including those not genotyped for p.Val1688del, or only those carrying the p.Val1688del. A number of tumors other than breast or ovarian cancers were observed in pedigrees #78, #305 and MON and included a total of 16 cases with different types of tumors with lung, prostate, and gastric cancers among others. None of these individuals, however, could be genotyped for p.Val1688del, for which the disease relatedness remains to be investigated.

To obtain a final assessment of p.Val1688del pathogenicity, we used as many different approaches as possible. Indeed, most of the approaches employed, such as co-occurrence with pathogenic mutations, LOH, histopathology data, and conservation analyses are much more powerful to obtain evidence in favor of neutrality rather than causality. Therefore, even though as few as one of the aforementioned approaches might prove successful under specific conditions, in general, the higher the number of independent approaches employed the more reliable are the results of the analysis. Conversely, studies based on single evidence obtained for a number of different variants usually force to a consensus revision of the scientific literature before the clinical relevance of each variant can be unequivocally determined. Using the approach designed by Goldgar,¹² we were able to integrate the results from five independent evidences. Under this model, we reached a highly significant result that, as such, can be readily translated in an unequivocal clinical message.

If we consider the whole cohort of our patients with BRCA1 pathogenic mutations, p.Val1688del represents the most frequent mutation in Northeast Italy. This will allow implementation of prescreen tests at least in those families coming from specific geographical subregions. p.Val1688del accounts for 15% (nine of 61) of families with a BRCA1 point mutation or few nucleotide deletions or insertions. Therefore, a single variant, even though a recurrent one, accounts for a relevant proportion of informative families comparable, for instance, with the one of major genomic rearrangements in the same gene.¹⁶ These data should prompt further research into the characterization of BRCA1 and BRCA2 variants contributing to filling the gap between families predicted to carry pathogenic mutations and those in which a molecular defect can actually be demonstrated.

	Authors’ Disclosures of Potential Conflicts of Interest

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
The author(s) indicated no potential conflicts of interest.

	AUTHOR CONTRIBUTIONS

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
Conception and design: Sandro Malacrida, Marco Montagna

Financial support: Emma D'Andrea

Provision of study materials or patients: Daniela Barana, Siranoush Manoukian, Cristina Oliani, Paolo Radice, Monica Barile, Emma D'Andrea

Collection and assembly of data: Simona Agata, Monia Callegaro, Cinzia Casella, Daniela Barana, Cristina Oliani, Chiara Menin

Data analysis and interpretation: Sandro Malacrida, Simona Agata, Monia Callegaro, Maria C. Scaini, Marco Montagna

Manuscript writing: Emma D'Andrea, Marco Montagna

Final approval of manuscript: Maria C. Scaini, Siranoush Manoukian, Paolo Radice, Monica Barile, Marco Montagna

	ACKNOWLEDGMENTS

 
We thank D. Zullato and M. Quaggio for technical assistance, and C. Case for help in preparing this article.

	NOTES

 
Supported by Ministero dell'Università e della Ricerca (MIUR), Ministero della Sanità - Programma Straordinario Ricerca Oncologica, Alleanza Contro il Cancro, Fondazione Cassa di Risparmio di Padova e Rovigo, and fellowships from "Accademia Nazionale dei Lincei" (S.A.) and Fondazione Italiana per la Ricerca sul Cancro (M.C.S).

Authors’ disclosures of potential conflicts of interest and author contributions are found at the end of this article.

	REFERENCES

TOP ABSTRACT INTRODUCTION PATIENTS AND METHODS RESULTS DISCUSSION Authors' Disclosures of... AUTHOR CONTRIBUTIONS REFERENCES

 
1. Miki Y, Swensen J, Shattuck-Eidens D, et al: A strong candidate for the breast and ovarian cancer susceptibility gene BRCA1. Science 266:66-71, 1994[Abstract/Free Full Text]

2. Chenevix-Trench G, Healey S, Lakhani S, et al: Genetic and histopathologic evaluation of BRCA1 and BRCA2 DNA sequence variants of unknown clinical significance. Cancer Res 66:2019-2027, 2006[Abstract/Free Full Text]

3. Judkins T, Hendrickson BC, Deffenbaugh AM, et al: Application of embryonic lethal or other obvious phenotypes to characterize the clinical significance of genetic variants found in trans with known deleterious mutations. Cancer Res 65:10096-10103, 2005[Abstract/Free Full Text]

4. Thompson D, Easton DF, Goldgar DE: A full-likelihood method for the evaluation of causality of sequence variants from family data. Am J Hum Genet 73:652-655, 2003[CrossRef][Medline]

5. Abkevich V, Zharkikh A, Deffenbaugh AM, et al: Analysis of missense variation in human BRCA1 in the context of interspecific sequence variation. J Med Genet 41:492-507, 2004[Abstract/Free Full Text]

6. Tavtigian SV, Deffenbaugh AM, Yin L, et al: Comprehensive statistical study of 452 BRCA1 missense substitutions with classification of eight recurrent substitutions as neutral. J Med Genet 43:295-305, 2006[Abstract/Free Full Text]

7. Carvalho MA, Marsillac SM, Karchin R, et al: Determination of cancer risk associated with germ line BRCA1 missense variants by functional analysis. Cancer Res 67:1494-1501, 2007[Abstract/Free Full Text]

8. Morris JR, Pangon L, Boutell C, et al: Genetic analysis of BRCA1 ubiquitin ligase activity and its relationship to breast cancer susceptibility. Hum Mol Genet 15:599-606, 2006[Abstract/Free Full Text]

9. Osorio A, Milne RL, Honrado E, et al: Classification of missense variants of unknown significance in BRCA1 based on clinical and tumor information. Hum Mutat 28:477-485, 2007[CrossRef][Medline]

10. Federico M, Maiorana A, Mangone L, et al: Identification of families with hereditary breast and ovarian cancer for clinical and mammographic surveillance: The Modena Study Group proposal. Breast Cancer Res Treat 55:213-221, 1999[CrossRef][Medline]

11. Montagna M, Dalla Palma M, Menin C, et al: Genomic rearrangements account for more than one-third of the BRCA1 mutations in northern Italian breast/ovarian cancer families. Hum Mol Genet 12:1055-1061, 2003[Abstract/Free Full Text]

12. Goldgar DE, Easton DF, Deffenbaugh AM, et al: Integrated evaluation of DNA sequence variants of unknown clinical significance: Application to BRCA1 and BRCA2. Am J Hum Genet 75:535-544, 2004[CrossRef][Medline]

13. Montagna M, Santacatterina M, Corneo B, et al: Identification of seven new BRCA1 germline mutations in Italian breast and breast/ovarian cancer families. Cancer Res 56:5466-5469, 1996[Abstract/Free Full Text]

14. Marroni F, Aretini P, D'Andrea E, et al: Evaluation of widely used models for predicting BRCA1 and BRCA2 mutations. J Med Genet 41:278-285, 2004[Free Full Text]

15. Finch A, Beiner M, Lubinski J, et al: Salpingo-oophorectomy and the risk of ovarian, fallopian tube, and peritoneal cancers in women with a BRCA1 or BRCA2 mutation. JAMA 296:185-192, 2006[Abstract/Free Full Text]

16. Agata S, Viel A, Della Puppa L, et al: Prevalence of BRCA1 genomic rearrangements in a large cohort of Italian breast and breast/ovarian cancer families without detectable BRCA1 and BRCA2 point mutations. Genes Chromosomes Cancer 45:791-797, 2006[CrossRef][Medline]

17. Montagna M, Santacatterina M, Torri A, et al: Identification of a 3 kb Alu-mediated BRCA1 gene rearrangement in two breast/ovarian cancer families. Oncogene 18:4160-4165, 1999[CrossRef][Medline]

18. Agata S, Dalla Palma M, Callegaro M, et al: Large genomic deletions inactivate the BRCA2 gene in breast cancer families. J Med Genet 42:e64, 2005[Abstract/Free Full Text]

19. Karchin R, Monteiro AN, Tavtigian SV, et al: Functional impact of missense variants in BRCA1 predicted by supervised learning. PLoS Comput Biol 3:e26, 2007[CrossRef][Medline]

20. Vallon-Christersson J, Cayanan C, Haraldsson K, et al: Functional analysis of BRCA1 C-terminal missense mutations identified in breast and ovarian cancer families. Hum Mol Genet 10:353-360, 2001[Abstract/Free Full Text]

21. Aretini P, D'Andrea E, Pasini B, et al: Different expressivity of BRCA1 and BRCA2: analysis of 179 Italian pedigrees with identified mutation. Breast Cancer Res Treat 81:71-79, 2003[CrossRef][Medline]

22. Antoniou A, Pharoah PD, Narod S, et al: Average risks of breast and ovarian cancer associated with BRCA1 or BRCA2 mutations detected in case Series unselected for family history: A combined analysis of 22 studies. Am J Hum Genet 72:1117-1130, 2003[CrossRef][Medline]

Submitted June 29, 2007; accepted September 17, 2007.

Related Editorial

• Genetic Variants of Uncertain Significance: Flies in the Ointment
  Susan Domchek and Barbara L. Weber
  JCO 2008 26: 16-17 [Full Text]

Related Correspondence

• Clinical Classification of BRCA1 DNA Missense Variants: H1686Q Is a Novel Pathogenic Mutation Occurring in the Ontogenetically Invariant THV Motif of the N-Terminal BRCT Domain
  Giuseppe Giannini, Carlo Capalbo, Laura Ottini, Amelia Buffone, Laura De Marchis, Elena Margaria, Domenico Vitolo, Enrico Ricevuto, Christian Rinaldi, Massimo Zani, Sergio Ferraro, Paolo Marchetti, Enrico Cortesi, Luigi Frati, Isabella Screpanti, and Alberto Gulino
  JCO 2008 26: 4212-4214 [Full Text]

This article has been cited by other articles:

				G. Giannini, C. Capalbo, L. Ottini, A. Buffone, L. De Marchis, E. Margaria, D. Vitolo, E. Ricevuto, C. Rinaldi, M. Zani, et al. Clinical Classification of BRCA1 DNA Missense Variants: H1686Q Is a Novel Pathogenic Mutation Occurring in the Ontogenetically Invariant THV Motif of the N-Terminal BRCT Domain J. Clin. Oncol., September 1, 2008; 26(25): 4212 - 4214. [Full Text] [PDF]

				M. Montagna and S. Malacrida In Reply J. Clin. Oncol., September 1, 2008; 26(25): 4214 - 4215. [Full Text] [PDF]

This Article Abstract Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Save to my personal folders Download to citation manager Rights & Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Malacrida, S. Articles by Montagna, M. Search for Related Content PubMed PubMed Citation Articles by Malacrida, S. Articles by Montagna, M. Related Articles Related Editorial Related Correspondence