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Background: A substantial fraction of familial colorectal cancer (CRC) and polyposis heritability remains unexplained. This study aimed to identify predisposing loci in patients with these disorders., Methods: Homozygosity mapping was performed using 222 563 SNPs in 302 index patients with various colorectal neoplasms and 3367 controls. Linkage analysis, exome and whole-genome sequencing were performed in a family affected by microsatellite stable CRCs. Candidate variants were genotyped in 10 554 cases and 21 480 controls. Gene expression was assessed at the mRNA and protein level., Results: Homozygosity mapping revealed a disease-associated region at 1q32.3 which was part of the linkage region 1q32.2-42.2 identified in the CRC family. This includes a region previously associated with risk of CRC. Sequencing identified the p.Asp1432Glu variant in the MIA3 gene (known as TANGO1 or TANGO) and 472 additional rare, shared variants within the linkage region. In both cases and controls the population frequency was 0.02% for this MIA3 variant. The MIA3 mutant allele showed predominant mRNA expression in normal, cancer and precancerous tissues. Furthermore, immunohistochemistry revealed increased expression of MIA3 in adenomatous tissues., Conclusions: Taken together, our two independent strategies associate genetic variations in chromosome 1q loci and predisposition to familial CRC and polyps, which warrants further investigation.

Objectives: To assess quality and reusability of coded cancer diagnoses in routine primary care data. To identify factors that influence data quality and areas for improvement., Methods: A dynamic cohort study in a Dutch network database containing 250,000 anonymized electronic medical records (EMRs) from 52 general practices was performed. Coded data from 2000 to 2011 for the three most common cancer types (breast, colon and prostate cancer) was compared to the Netherlands Cancer Registry., Measurements: Data quality is expressed in Standard Incidence Ratios (SIRs): the ratio between the number of coded cases observed in the primary care network database and the expected number of cases based on the Netherlands Cancer Registry. Ratios were multiplied by 100% for readability., Results: The overall SIR was 91.5% (95%CI 88.5-94.5) and showed improvement over the years. SIRs differ between cancer types: from 71.5% for colon cancer in males to 103.9% for breast cancer. There are differences in data quality (SIRs 76.2% - 99.7%) depending on the EMR system used, with SIRs up to 232.9% for breast cancer. Frequently observed errors in routine healthcare data can be classified as: lack of integrity checks, inaccurate use and/or lack of codes, and lack of EMR system functionality., Conclusions: Re-users of coded routine primary care Electronic Medical Record data should be aware that 30% of cancer cases can be missed. Up to 130% of cancer cases found in the EMR data can be false-positive. The type of EMR system and the type of cancer influence the quality of coded diagnosis registry. While data quality can be improved (e.g. through improving system design and by training EMR system users), re-use should only be taken care of by appropriately trained experts., (Copyright © 2016. Published by Elsevier B.V.)

Cancer genetic counselees receive individualized information regarding heightened risks and medical recommendations which is also relevant for their at-risk relatives. Unfortunately, counselees often insufficiently inform these relatives. We designed an intervention aimed at improving counselees' knowledge regarding which at-risk relatives to inform and what information to disclose, their motivation to disclose, and their self-efficacy. The intervention, offered by telephone by trained psychosocial workers, is based on the principles of Motivational Interviewing. Phase 1 of the intervention covers agenda setting, exploration, and evaluation, and phase 2 includes information provision, enhancing motivation and self-efficacy, and brainstorming for solutions to disseminate information within the family. Fidelity and acceptability of the intervention were assessed using recordings of intervention sessions and by counselee self-report. A total of 144 counselees participated. Psychosocial workers (n = 5) delivered the intervention largely as intended. Counselees highly appreciated the content of the intervention and the psychosocial workers who delivered the intervention. In the sessions, psychosocial workers provided additional and/or corrective information, and brainstorming for solutions was performed in 70 %. These results indicate that this intervention is feasible and warrants testing in clinical practice. For this, a randomized controlled trial is currently in progress to test the intervention's efficacy., Competing Interests: Eveline de Geus, Willem Eijzenga, Fred H. Menko, Rolf H. Sijmons, Hanneke C. J. M. de Haes, Cora M. Aalfs and Ellen M. A. Smets declares that they have no competing interests. Human Studies and Informed Consent All procedures followed were in accordance with the ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000 (5). Informed consent was obtained from all patients before inclusion in the study. Animal Studies No animal studies were carried out by the authors for this article.

We have developed a tool for detecting single exon copy-number variations (CNVs) in targeted next-generation sequencing data: CoNVaDING (Copy Number Variation Detection In Next-generation sequencing Gene panels). CoNVaDING includes a stringent quality control (QC) metric, that excludes or flags low-quality exons. Since this QC shows exactly which exons can be reliably analyzed and which exons are in need of an alternative analysis method, CoNVaDING is not only useful for CNV detection in a research setting, but also in clinical diagnostics. During the validation phase, CoNVaDING detected all known CNVs in high-quality targets in 320 samples analyzed, giving 100% sensitivity and 99.998% specificity for 308,574 exons. CoNVaDING outperforms existing tools by exhibiting a higher sensitivity and specificity and by precisely identifying low-quality samples and regions., (© 2016 WILEY PERIODICALS, INC.)

Next-generation sequencing in clinical diagnostics is providing valuable genomic variant data, which can be used to support healthcare decisions. In silico tools to predict pathogenicity are crucial to assess such variants and we have evaluated a new tool, Combined Annotation Dependent Depletion (CADD), and its classification of gene variants in Lynch syndrome by using a set of 2,210 DNA mismatch repair gene variants. These had already been classified by experts from InSiGHT's Variant Interpretation Committee. Overall, we found CADD scores do predict pathogenicity (Spearman's ρ = 0.595, P < 0.001). However, we discovered 31 major discrepancies between the InSiGHT classification and the CADD scores; these were explained in favor of the expert classification using population allele frequencies, cosegregation analyses, disease association studies, or a second-tier test. Of 751 variants that could not be clinically classified by InSiGHT, CADD indicated that 47 variants were worth further study to confirm their putative pathogenicity. We demonstrate CADD is valuable in prioritizing variants in clinically relevant genes for further assessment by expert classification teams., (© 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.)

The clinical classification of hereditary sequence variants identified in disease-related genes directly affects clinical management of patients and their relatives. The International Society for Gastrointestinal Hereditary Tumours (InSiGHT) undertook a collaborative effort to develop, test and apply a standardized classification scheme to constitutional variants in the Lynch syndrome-associated genes MLH1, MSH2, MSH6 and PMS2. Unpublished data submission was encouraged to assist in variant classification and was recognized through microattribution. The scheme was refined by multidisciplinary expert committee review of the clinical and functional data available for variants, applied to 2,360 sequence alterations, and disseminated online. Assessment using validated criteria altered classifications for 66% of 12,006 database entries. Clinical recommendations based on transparent evaluation are now possible for 1,370 variants that were not obviously protein truncating from nomenclature. This large-scale endeavor will facilitate the consistent management of families suspected to have Lynch syndrome and demonstrates the value of multidisciplinary collaboration in the curation and classification of variants in public locus-specific databases.

Lynch syndrome (LS) is characterised by the development of colorectal cancer, endometrial cancer and various other cancers, and is caused by a mutation in one of the mismatch repair genes: MLH1, MSH2, MSH6 or PMS2. In 2007, a group of European experts (the Mallorca group) published guidelines for the clinical management of LS. Since then substantial new information has become available necessitating an update of the guidelines. In 2011 and 2012 workshops were organised in Palma de Mallorca. A total of 35 specialists from 13 countries participated in the meetings. The first step was to formulate important clinical questions. Then a systematic literature search was performed using the Pubmed database and manual searches of relevant articles. During the workshops the outcome of the literature search was discussed in detail. The guidelines described in this paper may be helpful for the appropriate management of families with LS. Prospective controlled studies should be undertaken to improve further the care of these families.

Purpose: The aim of this study is to further understand the status of BRCA1 and BRCA2 mutation among Chinese high-risk breast cancer patients in multiple-ethnic regions of China., Methods: A total of 79 blood samples of high-risk breast cancer patients from Xinjiang Uyghur autonomous region were analyzed by PCR-DHPLC sequencing analysis., Results: Analysis with full length of the two genes identified a total of 6 deleterious mutations (2073delA, 2394C-T [Q759X] and IVS16+1G>A in BRCA1; 1627A-T [K467X], 6873delCTCC and 9481delA in BRCA2) in this cohort. The prevalence of BRCA1/2 germline mutation was about 7.6% (6/79) in the Xinjiang multiple ethnic region of China. Among them, 3 novel deleterious mutations, 2073delA in BRCA1 (Han ethnic Chinese) and BRCA2 variants 6873delCTCC and 9481delA (both are Kazakh ethnic Chinese), were identified and they had never been reported in breast cancer information core (BIC) database before. 2394C-T (Q759X) and IVS16+1G>A, in BRCA1 and BRCA2 variants 1627A-T were previously reported in other populations but not Chinese. Among 6 of the BRCA-related tumors, three BRCA1- and one BRCA2-associated tumors were in triple negative (estrogen receptor, progesterone receptor, and HER2 negative expressed) status and exhibited a high tumor grade. So far none of these 6 deleterious mutations were reported in ethnic Han Chinese., Conclusion: BRCA germline mutation in Chinese multiple ethnicity region may exhibit different genotypes compared to ethnic Han Chinese in other regions. These differences may arise from interaction of genetic background and environmental factors.

The range of commercially available array platforms and analysis software packages is expanding and their utility is improving, making reliable detection of copy-number variants (CNVs) relatively straightforward. Reliable interpretation of CNV data, however, is often difficult and requires expertise. With our knowledge of the human genome growing rapidly, applications for array testing continuously broadening, and the resolution of CNV detection increasing, this leads to great complexity in interpreting what can be daunting data. Correct CNV interpretation and optimal use of the genotype information provided by single-nucleotide polymorphism probes on an array depends largely on knowledge present in various resources. In addition to the availability of host laboratories' own datasets and national registries, there are several public databases and Internet resources with genotype and phenotype information that can be used for array data interpretation. With so many resources now available, it is important to know which are fit-for-purpose in a diagnostic setting. We summarize the characteristics of the most commonly used Internet databases and resources, and propose a general data interpretation strategy that can be used for comparative hybridization, comparative intensity, and genotype-based array data., Competing Interests: Statement: The authors declare no conflict of interest.

The only known genetic causes of hereditary diffuse gastric cancer (HDGC) are germline mutations in the CDH1 gene.- CDH1 mutation carriers have a lifetime risk of 70-80% of developing diffuse gastric cancer. As periodic gastric surveillance is of limited value in detecting early stages of HDGC, prophylactic gastrectomy is advised for this patient group. This group is small and little is known about other types of familial gastric cancer. The Dutch Working Group on Hereditary Gastric Cancer has formulated criteria for various aspects of medical care for families and individuals at high risk of developing gastric cancer, including criteria for diagnostics and periodic gastric surveillance. In order to optimize the care and increase the knowledge on hereditary gastric cancer it is important to centralize medical care for these patients.

In this paper we review clinical and genetic aspects of testicular germ cell tumours (TGCTs). TGCT is the most common type of malignant disorder in men aged 1540 years. Its incidence has increased sharply in recent years. Fortunately, survival of patients with TGCT has improved enormously, which can chiefly be attributed to the cisplatin-based polychemotherapy that was introduced in the nineteen eighties to treat patients with metastasized TGCT. In addition, new strategies have been developed in the surgical approach to metastasized/non-metastasized TGCT and alterations have been made to the radiotherapy technique and radiation dose for seminoma. Family history of TGCT is among the strongest risk factors for this tumour type. Although this fact and others suggest the existence of genetic predisposition to develop TGCT, no germline mutations conferring high risk of developing TGCT have been identified so far. A small deletion, referred to as gr/gr, identified on the Y chromosome is probably associated with only a modest increase in TGCT risk, and linkage of familial TGCT to the Xq27 region has not been confirmed yet. Whether highly penetrant TGCT-predisposing mutations truly exist or familial clustering of TGCT can be explained by combinations of weak predispositions, shared in utero or postnatal risks factors and coincidental somatic mutations is an intriguing puzzle, still waiting to be solved.

Hereditary non-polyposis colorectal carcinoma (HNPCC) is an autosomal dominant disorder associated with colorectal and endometrial cancer and a range of other tumor types. Germline mutations in the DNA mismatch repair (MMR) genes, particularly MLH1, MSH2, and MSH6, underlie this disorder. The vast majority of these HNPCC-associated mutations have been proven, or assumed, given the family history of cancer, to be transmitted through several generations. To the best of our knowledge, only a single case of a de novo germline MMR gene mutation (in MSH2) has been reported till now. Here, we report a patient with a de novo mutation in MLH1. We identified a MLH1 Q701X truncating mutation in the blood lymphocytes of a male who had been diagnosed with rectal cancer at the age of 35. His family history of cancer was negative for the first- and second-degree relatives. The mutation could not be detected in the patient' parents and sibling and paternity was confirmed with a set of highly polymorphic markers. Non-penetrance and small family size is the common explanation of verified negative family histories of cancer in patients with a germline MMR gene mutation. However, in addition to some cases explained by non-paternity, de novo germline mutations should be considered as a possible explanation as well. As guidelines that stress not to restrict MMR gene mutation testing to patients with a positive family history are more widely introduced, more cases of de novo MMR gene germline mutations may be revealed.

Background: In patients with hereditary or constitutional chromosomal anomalies, testicular carcinoma can develop sporadically or on the basis of an underlying hereditary genetic defect. Greater knowledge of these genetic defects would provide more insight into the molecular pathways that lead to testicular carcinoma. To the authors' knowledge, little attention has been paid to date to the comorbid occurrence of testicular carcinoma in patients with hereditary disorders or constitutional chromosomal anomalies., Methods: The authors performed a review of the literature., Results: Twenty-five different hereditary disorders or constitutional chromosomal anomalies have been reported in patients who developed seminomatous or nonseminomatous testicular carcinoma., Conclusions: Although most of these malignancies were too rare to enable the detection of statistically significant correlations between the chromosomal/hereditary disorder and the testicular tumor, it was striking that many of the patients had also other urogenital abnormalities. Susceptibility to urogenital abnormalities seems to disrupt normal urogenital differentiation and suggests a correlation with testicular dysgenesis and, thus, also with testicular carcinoma. Other evidence of causal involvement has been found in the field of tumor cytogenetics. Some of the genes responsible for hereditary disorders have been mapped to regions that are of interest in the development of sporadic testicular carcinoma. Molecular studies on candidate genes will be required to provide definite answers. Completion of the human gene map and the availability of advanced gene arrays and bioinformatics are expected to greatly facilitate further exploration of the role of hereditary genetic defects in testicular carcinoma., (Copyright 2003 American Cancer Society)

This report focuses on low-penetrance genes that are associated with colorectal adenoma and/or cancer or that are in strong linkage disequilibrium with colorectal adenoma and/or cancer causing variants. A pooled analysis was performed for 30 polymorphisms in 20 different genes that have been reported in more than one colorectal adenoma or cancer study. An association with colorectal cancer was found for seven polymorphisms in seven genes reported in more than one study; no associations were found with colorectal adenoma. Four of the polymorphisms exhibited an increased colorectal cancer risk [GSTT1, NAT2 (phenotype), HRAS1, and ALDH2]. Two others [MTHFR, Tp53 (intron 3)] exhibited a decreased risk. For the tumor necrosis factor (TNF)a polymorphism of the TNF-alpha gene, one allele was associated with an increased risk (a2 allele) and two other TNFa alleles with decreased risks (a5 and a13 allele). No association with colorectal adenoma and/or cancer was detected for 23 other polymorphisms in 15 genes. However, of all 30 polymorphisms, only three pooled analyses had sufficiently large samples to confirm (MTHFR) or to exclude (GSTM1 and NAT2 genotype) the association with a P < 0.0026 and a power of 90%. Eighteen polymorphisms in 15 genes were each described in only one study, all with very small sample sizes. For 11 polymorphisms in 10 of these genes, an association with colorectal adenoma and/or cancer was found. Only simultaneous genotyping and combined analysis of different polymorphisms in large numbers of patients and controls, stratified by ethnicity, gender, and tumor localization and taking relevant dietary and lifestyle habits into account, will make it possible to describe the exact relations between polymorphisms and colorectal cancer susceptibility with an adequate power.

Background: The association with histocompatibility antigens (HLA), in particular Class II genes (DQB1, DRB1), has recently been suggested to be one of the genetic factors involved in testicular germ cell tumor (TGCT) development. The current study, which uses genotyping of microsatellite markers, was designed to replicate previous associations., Methods: In 151 patients, along with controls comprising parents or spouses, the HLA region (particularly Class II) on chromosome 6p21 was genotyped for a set of 15 closely linked microsatellite markers., Results: In both patients and controls, strong linkage disequilibrium was observed in the genotyped region, indicating that similar haplotypes are likely to be identical by descent. However, association analysis and the transmission disequilibrium test did not show significant results. Haplotype sharing statistics, a haplotype method that derives extra information from phase and single marker tests, did not show differences in haplotype sharing between patients and controls., Conclusion: The current genotyping study did not confirm the previously reported association between HLA Class II genes and TGCT. As the HLA alleles for which associations were reported are also prevalent in the Dutch populations, these associations are likely to be nonexistent or much weaker than previously reported., (Copyright 2002 American Cancer Society.)

The MSH6 gene is one of the mismatch-repair genes involved in hereditary nonpolyposis colorectal cancer (HNPCC). Three hundred sixteen individuals who were known or suspected to have HNPCC were analyzed for MSH6 germline mutations. For 25 index patients and 8 relatives with MSH6 variants, molecular and clinical features are described. For analysis of microsatellite instability (MSI), the five consensus markers were used. Immunohistochemical analysis of the MLH1, MSH2, and MSH6 proteins was performed. Five truncating MSH6 mutations, of which one was detected seven times, were found in 12 index patients, and 10 MSH6 variants with unknown pathogenicity were found in 13 index patients. Fourteen (54%) of 26 colorectal cancers (CRCs) and endometrial cancers showed no, or only weak, MSI. Twelve of 18 tumors of truncating-mutation carriers and 3 of 17 tumors of missense-mutation carriers showed loss of MSH6 staining. Six of the families that we studied fulfilled the original Amsterdam criteria; most families with MSH6, however, were only suspected to have HNPCC. In families that did not fulfill the revised Amsterdam criteria, the prevalence of MSH6 variants is about the same as the prevalence of those in MLH1/MSH2. Endometrial cancer and/or atypical hyperplasia were diagnosed in 8 of 12 female carriers of MSH6 truncating mutations. Most CRCs were localized distally in the colon. Although, molecularly, missense variants are labeled as doubtfully pathogenic, clinical data disclose a great resemblance between missense-variant carriers and truncating-mutation carriers. We conclude that, in all patients suspected to have HNPCC, MSH6-mutation analysis should be considered. Neither MSI nor immunohistochemistry should be a definitive selection criterion for MSH6-mutation analysis.