scholarly journals Same MSH2 Gene Mutation But Variable Phenotypes in 2 Families With Lynch Syndrome: Two Case Reports and Review of Genotype-Phenotype Correlation

2018 ◽  
Vol 11 ◽  
pp. 117954761775394 ◽  
Author(s):  
Raffaella Liccardo ◽  
Marina De Rosa ◽  
Francesca Duraturo

Lynch syndrome is an autosomal dominant syndrome that can be subdivided into Lynch syndrome I, or site-specific colonic cancer, and Lynch syndrome II, or extracolonic cancers, particularly carcinomas of the stomach, endometrium, biliary and pancreatic systems, and urinary tract. Lynch syndrome is associated with point mutations and large rearrangements in DNA MisMatch Repair ( MMR) genes. This syndrome shows a variable phenotypic expression in people who carry pathogenetic mutations. So far, a correlation in genotype-phenotype has not been definitely established. In this study, we describe 2 Lynch syndrome cases presenting with the same genotype but different phenotypes and discuss possible reasons for this.

2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Jose Miguel Moreno-Ortiz ◽  
María de la Luz Ayala-Madrigal ◽  
Jorge Román Corona-Rivera ◽  
Manuel Centeno-Flores ◽  
Víctor Maciel-Gutiérrez ◽  
...  

Background. Lynch Syndrome (LS) is characterized by germline mutations in the DNA mismatch repair (MMR) genesMLH1,MSH2,MSH6,andPMS2. This syndrome is inherited in an autosomal dominant pattern and is characterized by early onset colorectal cancer (CRC) and extracolonic tumors. The aim of this study was to identify mutations inMMRgenes in three Mexican patients with LS.Methods. Immunohistochemical analysis was performed as a prescreening method to identify absent protein expression. PCR, Denaturing High Performance Liquid Chromatography (dHPLC), and Sanger sequencing complemented the analysis.Results. Two samples showed the absence of nuclear staining for MLH1 and one sample showed loss of nuclear staining for MSH2. The mutations found inMLH1gene were c.2103+1G>C in intron 18 and compound heterozygous mutants c.1852_1854delAAG (p.K618del) and c.1852_1853delinsGC (p.K618A) in exon 16. In theMSH2gene, we identified mutation c.638dupT (p.L213fs) in exon 3.Conclusions. This is the first report of mutations in MMR genes in Mexican patients with LS and these appear to be novel.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Francesca Duraturo ◽  
Angela Cavallo ◽  
Raffaella Liccardo ◽  
Bianca Cudia ◽  
Marina De Rosa ◽  
...  

Lynch syndrome is associated with germ-line mutations in the DNA mismatch repair (MMR) genes, mainlyMLH1andMSH2. Most of the mutations reported in these genes to date are point mutations, small deletions, and insertions. Large genomic rearrangements in the MMR genes predisposing to Lynch syndrome also occur, but the frequency varies depending on the population studied on average from 5 to 20%. The aim of this study was to examine the contribution of large rearrangements in theMLH1andMSH2genes in a well-characterised series of 63 unrelated Southern Italian Lynch syndrome patients who were negative for pathogenic point mutations in theMLH1,MSH2, andMSH6genes. We identified a large novel deletion in theMSH2gene, including exon 6 in one of the patients analysed (1.6% frequency). This deletion was confirmed and localised by long-range PCR. The breakpoints of this rearrangement were characterised by sequencing. Further analysis of the breakpoints revealed that this rearrangement was a product of Alu-mediated recombination. Our findings identified a novel Alu-mediated rearrangement withinMSH2gene and showed that large deletions or duplications inMLH1andMSH2genes are low-frequency mutational events in Southern Italian patients with an inherited predisposition to colon cancer.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Markku Aarnio

Lynch syndrome (LS) is characterized by an autosomal dominant inheritance of the early onset of colorectal cancer (CRC) and endometrial cancer, as well as increased risk for several other cancers including gastric, urinary tract, ovarian, small bowel, biliary tract, and brain tumors. The syndrome is due to a mutation in one of the four DNA mismatch repair (MMR) genes MLH1, MSH2, MSH6, or PMS2. The majority of LS patients and families can now be identified, and the underlying mutation detected using genetic diagnostics. Regular surveillance for CRC and endometrial cancer has proved beneficial for mutation carriers. However, screening for other tumors is also recommended even though experiences in the screening of these tumors is limited. Prophylactic colectomy, prophylactic hysterectomy, and bilateral salpingo-oophorectomy may be reasonable options for selected patients with LS. This paper describes the features and management of LS.


2008 ◽  
Vol 31 (4) ◽  
pp. 12
Author(s):  
A J Hyde ◽  
D Fontaine ◽  
R C Green ◽  
M Simms ◽  
P S Parfrey ◽  
...  

Background: Lynch Syndrome is an autosomal dominant trait that accounts forapproximately 3% of all cases of colorectal cancer (CRC). It is caused by mutations in DNA mismatch repair (MMR) genes, most commonly MLH1 or MSH2. These MMR defects cause high levels of microsatellite instability (MSI-H) in the tumours. MSI testing of all CRCs to identify potential Lynch Syndrome cases is not practical, so the Bethesda Guidelines, which use clinical and pathological features, were created to identify those tumours most likely to be MSI-H^1. In 2007 Jenkins et. al. created MsPath, a tool based on the pathological features described in the rarely used 3^rd Bethesda criterion, to improve prediction of MSI-H tumours among CRC cases diagnosed before age 60 years^2. Methods: We collected a population-based cohort of 716 CRC cases diagnosed before age 75 years in Newfoundland. For each of these cases we collected family history, performed MSI analysis, and scored a number of pathological features for the purpose of evaluating the accuracy of the Bethesda Criteria and MsPath at predicting MSI-H tumours. Results: Our work validates the MsPath tool in the Newfoundland population for the same age group used to create the tool. We found it identified MSI-H cases with a sensitivity of 95% and specificity of 35% in our population of CRCcases diagnosed before age 60 years (n=290). We also tested this tool on our older population of CRCcases, diagnosed at ages 60 to 74 years (n=426). We found it to be at least as predictive in this population,with a sensitivity of 95% and a specificity of 42%. We then used our entire cohort (N=716) to compare MsPath with the other Bethesda criteria.Bethesda criteria 1, 2, 4 and 5 together predicted MSI-H cases with a sensitivity of 67% and a specificity of 51%. MsPath was better at identifying these cases, with a sensitivity of 95% and a specificity of 39%. Conclusions: We conclude that MsPath can be extended to include patients diagnosed with CRC before age 75 years. As well, we have found that MsPath is a better predictive tool than the Revised Bethesda Guidelines for identifying MSI-H cases within a population-based setting of colorectal cancer. References: 1. Umar, A. et. al. J Natl Cancer Inst 2004;96:261-8 2.Jenkins, M.A. et. al. Gastroenterology 2007;133:48-56


2021 ◽  
pp. 000313482110318
Author(s):  
Aaron J. Arroyave ◽  
Alan W. Good ◽  
Andrew J. Ward ◽  
Amila L. Orucevic ◽  
James M. McLoughlin

Lynch syndrome (LS) is a common genetic syndrome characterized by pathogenic mutations of DNA mismatch repair genes resulting in a hereditary predisposition to cancer. While typically associated with colonic and endometrial cancer, LS additionally influences the development of many other malignancies. The Amsterdam II and Revised Bethesda Guidelines are the established clinical criteria for diagnosing LS. These guidelines are based on the most general characteristics of LS and do not address specific characteristics of the less commonly LS-associated malignancies. For individuals that present initially with a non-colon and non-endometrial malignancy, recommendations and guidelines on when to consider screening for LS are limited. Therefore, it is essential that clinicians are familiar with distinct LS-associated patient- and tumor-specific characteristics, especially of the less common LS-associated cancers, so that LS’s diagnosis is not missed. In this review article, we focus on extra-colonic and extra-endometrial LS-associated cancers, paying particular attention to any established or currently investigated cancer features that help raise suspicion for LS and potentially lead to its earlier diagnosis. This review will also discuss current guidelines specific to each LS-associated malignancy.


2021 ◽  
pp. 1-21
Author(s):  
Antonio Atalaia ◽  
Rabah Ben Yaou ◽  
Karim Wahbi ◽  
Annachiara De Sandre-Giovannoli ◽  
Corinne Vigouroux ◽  
...  

Background: Variants in the LMNA gene, encoding lamins A/C, are responsible for a growing number of diseases, all of which complying with the definition of rare diseases. LMNA-related disorders have a varied phenotypic expression with more than 15 syndromes described, belonging to five phenotypic groups: Muscular Dystrophies, Neuropathies, Cardiomyopathies, Lipodystrophies and Progeroid Syndromes. Overlapping phenotypes are also reported. Linking gene and variants with phenotypic expression, disease mechanisms, and corresponding treatments is particularly challenging in laminopathies. Treatment recommendations are limited, and very few are variant-based. Objective: The Treatabolome initiative aims to provide a shareable dataset of existing variant-specific treatment for rare diseases within the Solve-RD EU project. As part of this project, we gathered evidence of specific treatments for laminopathies via a systematic literature review adopting the FAIR (Findable, Accessible, Interoperable, and Reusable) guidelines for scientific data production. Methods: Treatments for LMNA-related conditions were systematically collected from MEDLINE and Embase bibliographic databases and clinical trial registries (Cochrane Central Registry of Controlled Trials, clinicaltrial.gov and EudraCT). Two investigators extracted and analyzed the literature data independently. The included papers were assessed using the Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence. Results: From the 4783 selected articles by a systematic approach, we identified 78 papers for our final analysis that corresponded to the profile of data defined in the inclusion and exclusion criteria. These papers include 2 guidelines/consensus papers, 4 meta-analyses, 14 single-arm trials, 15 case series, 13 cohort studies, 21 case reports, 8 expert reviews and 1 expert opinion. The treatments were summarized electronically according to significant phenome-genome associations. The specificity of treatments according to the different laminopathic phenotypical presentations is variable. Conclusions: We have extracted Treatabolome-worthy treatment recommendations for patients with different forms of laminopathies based on significant phenome-genome parings. This dataset will be available on the Treatabolome website and, through interoperability, on genetic diagnosis and treatment support tools like the RD-Connect’s Genome Phenome Analysis Platform.


2017 ◽  
Vol 137 (2) ◽  
pp. 89-92 ◽  
Author(s):  
David McLaughlin ◽  
Ron Kerr

Type 2B von Willebrand disease is a rare bleeding condition resulting in thrombocytopenia and a reduction in large VWF multimers. It usually has an autosomal dominant pattern of inheritance. We report the management of a patient with type 2B von Willebrand disease, whose diagnosis was confirmed by demonstration of a R1306W mutation, through her first pregnancy. The patient's von Willebrand factor (VWF) antigen and VWF ristocetin cofactor levels rose throughout pregnancy, with an associated drop in the platelet count. The patient was successfully managed through labour to a surgical delivery with VWF concentrate, platelet transfusions and tranexamic acid. The patient delivered a male baby who was found to have inherited type 2B von Willebrand disease and had a significant cephalhaematoma at delivery. The baby was managed with VWF concentrate and platelet transfusions and made a full recovery. There is a lack of evidence to guide the best management of pregnant patients with type 2B von Willebrand disease. We adopted a pragmatic management plan, in keeping with other published case reports. To the best of our knowledge, this is the first case report in which the child was found to have inherited type 2B von Willebrand disease and encountered bleeding problems, making this case unique amongst the published literature.


2013 ◽  
Vol 227 (2) ◽  
pp. 342-348 ◽  
Author(s):  
Stefano Bertolini ◽  
Livia Pisciotta ◽  
Claudio Rabacchi ◽  
Angelo B. Cefalù ◽  
Davide Noto ◽  
...  

2020 ◽  
Vol 9 (1) ◽  
pp. 2
Author(s):  
Tal Domanovich-Asor ◽  
Yair Motro ◽  
Boris Khalfin ◽  
Hillary A. Craddock ◽  
Avi Peretz ◽  
...  

Antimicrobial resistance (AMR) in Helicobacter pylori is increasing and can result in treatment failure and inappropriate antibiotic usage. This study used whole genome sequencing (WGS) to comprehensively analyze the H. pylori resistome and phylogeny in order to characterize Israeli H. pylori. Israeli H. pylori isolates (n = 48) underwent antimicrobial susceptibility testing (AST) against five antimicrobials and WGS analysis. Literature review identified 111 mutations reported to correlate with phenotypic resistance to these antimicrobials. Analysis was conducted via our in-house bioinformatics pipeline targeting point mutations in the relevant genes (pbp1A, 23S rRNA, gyrA, rdxA, frxA, and rpoB) in order to assess genotype-to-phenotype correlation. Resistance rates of study isolates were as follows: clarithromycin 54%, metronidazole 31%, amoxicillin 10%, rifampicin 4%, and levofloxacin 2%. Genotype-to-phenotype correlation was inconsistent; for every analyzed gene at least one phenotypically susceptible isolate was found to have a mutation previously associated with resistance. This was also observed regarding mutations commonly used in commercial kits to diagnose AMR in H. pylori cases. Furthermore, 11 novel point mutations associated with a resistant phenotype were detected. Analysis of a unique set of H. pylori isolates demonstrates that inferring resistance phenotypes from WGS in H. pylori remains challenging and should be optimized further.


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