scholarly journals A novel frequent BRCA1 recurrent variant c.5117G > A (p.Gly1206Glu) identified after 20 years of BRCA1/2 research in the Baltic region: cohort study and literature review

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
P. Loza ◽  
A. Irmejs ◽  
Z. Daneberga ◽  
E. Miklasevics ◽  
E. Berga-Svitina ◽  
...  

Abstract Background Several recent studies in the Baltic region have found extended spectrum of pathogenic variants (PV) of the BRCA1/2 genes. The aim of current study is to analyze the spectrum of the BRCA1/2 PV in population of Latvia and to compare common PV between populations of the Baltic region. Methods We present a cohort of 9543 unrelated individuals including ones with cancer and unaffected individuals from population of Latvia, who were tested for three most common BRCA1 founder PV. In second line testing, 164 founder negative high-risk individuals were tested for PV of the BRCA1/2 using next generation sequencing (NGS). Local spectrum of the BRCA1/2 PV was compared with the Baltic region by performing a literature review. Results Founder PV c.5266dupC, c.4035delA or c.181 T > G was detected in 369/9543 (3.9%) cases. Other BRCA1/2 PV were found in 44/164 (26.8%) of NGS cases. Four recurrent BRCA1 variants c.5117G > A (p.Gly1706Glu), c.4675G > A (p.Glu1559Lys), c.5503C > T (p.Arg1835*) and c.1961delA (p.Lys654fs) were detected in 18/44 (41.0%), 5/44 (11.4%), 2/44 (4.5%) and 2/44 (4.5%) cases respectively. Additionally, 11 BRCA1 PV and six BRCA2 PV were each found in single family. Conclusions By combining three studies by our group of the same cohort in Latvia, frequency of the BRCA1/2 PV for unselected breast and ovarian cancer cases is 241/5060 (4.8%) and 162/1067 (15.2%) respectively. The frequency of three “historical” founder PV is up to 87.0% (369/424). Other non-founder PV contribute to at least 13.0% (55/424) and this proportion probably will rise by increasing numbers of the BRCA1/2 sequencing. In relative numbers, c.5117G > A is currently the third most frequent PV of the BRCA1 in population of Latvia, overcoming previously known third most common founder variant c.181 T > G. In addition to three BRCA1 founder PV, a total of five recurrent BRCA1 and two recurrent BRCA2 PV have been reported in population of Latvia so far. Many of the BRCA1/2 PV reported in Latvia are shared among other populations of the Baltic region.

Genes ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 60
Author(s):  
Valeria D’Argenio ◽  
Federica Cariati ◽  
Rossella Tomaiuolo

The current diagnostic path of infertile couples is long lasting and often ineffective. Genetic tests, in particular, appear as a limiting step due to their jeopardized use on one side, and to the limited number of genes evaluated on the other. In this context, the development and diffusion, also in routine diagnostic settings, of next generation sequencing (NGS)-based methods for the analyses of several genes in multiple subjects at a time is improving the diagnostic sensitivity of molecular analyses. Thus, we developed One4Two®, a custom NGS panel to optimize the diagnostic journey of infertile couples. The panel validation was carried out in three steps analyzing a total of 83 subjects. Interestingly, all the previously identified variants were confirmed, assessing the analytic sensitivity of the method. Moreover, additional pathogenic variants have been identified underlying the diagnostic efficacy of the proposed method. One4Two® allows the simultaneous analysis of infertility-related genes, disease-genes of common inherited diseases, and of polymorphisms related to therapy outcome. Thus, One4Two® is able to improve the diagnostic journey of infertile couples by simplifying the whole process not only for patients, but also for laboratories and reproduction specialists moving toward an even more personalized medicine.


2021 ◽  
Author(s):  
Ruwangi Dissanayake ◽  
Nayana Samarasinghe ◽  
Samantha Waidyanatha ◽  
Sajeewani Pathirana ◽  
Vajira HW Dissanayake ◽  
...  

Abstract Background. Iron overload (IO) is a complication in transfusion dependent beta thalassaemmia (TDT). Pathogenic variants in genes involving iron metabolism may confer increased risk of IO. The objective of this study was to determine the magnitude of the cardiac and hepatic IO and determine whether pathogenic variants in HFE, SLC40A1 and TFR2 genes increase the risk of IO in a cohort of TDT patients in Sri Lanka.Materials and Methods. Fifty-seven (57) patients with TDT were recruited for this study. Serum ferritin was done once in 3 months for one year in all. Those who were ≥ 8 years of age underwent T2* MRI of the liver and heart. Fifty-two (52) patients underwent next generation sequencing (NGS) to identify pathogenic variants in HBB, HFE, SLC40A1 and TFR2 genes.Results. The mean age (SD) of this cohort was 9.5 (±4.6) years. It comprised of 30 (52.6%) boys and 27 (47.4%) girls. The mean serum ferritin was 3405 (±2670.5) ng/dl. Hepatic IO was seen in 38 (95%) patients and cardiac IO was seen in 17 (42.5%) patients. All patients with cardiac IO were asymptomatic and had normal echocardiogrammes. There was no statistically significant correlation between serum ferritin and hepatic or cardiac IO.32 (61.5%), 18 (34.6%), 2 (3.8%) of patients were homozygotes, compound heterozygotes and heterozygotes for pathogenic variants in the HBB gene. 9 (17.3%) and 3 (5.8%) patients were heterozygotes for pathogenic variants of HFE and SLC40A1 genes respectively. There were no pathogenic variants for the TfR2 gene. The heterozygotes of the pathogenic variants of the HFE and SLC40A1 genes were not at increased risk of IO.Conclusions. Cardiac T2* MRI helps to detect cardiac IO prior to the onset of symptoms when the echocardiogramme is normal. It is important to perform hepatic and cardiac MRI T2* to detect IO in patients with TDT.


2020 ◽  
Vol 21 (4) ◽  
pp. 1290
Author(s):  
Jennifer S. Winn ◽  
Zachary Hasse ◽  
Michael Slifker ◽  
Jianming Pei ◽  
Sebastian M. Arisi-Fernandez ◽  
...  

We studied genomic alterations in 19 inflammatory breast cancer (IBC) patients with advanced disease using samples of tissue and paired blood serum or plasma (cell-free DNA, cfDNA) by targeted next generation sequencing (NGS). At diagnosis, the disease was triple negative (TN) in eleven patients (57.8%), ER+ Her2- IBC in six patients (31.6%), ER+ Her2+ IBC in one patient (5.3%), and ER- Her2+ IBC in one other patient (5.3%). Pathogenic or likely pathogenic variants were frequently detected in TP53 (47.3%), PMS2 (26.3%), MRE11 (26.3%), RB1 (10.5%), BRCA1 (10.5%), PTEN (10.5%) and AR (10.5%); other affected genes included PMS1, KMT2C, BRCA2, PALB2, MUTYH, MEN1, MSH2, CHEK2, NCOR1, PIK3CA, ESR1 and MAP2K4. In 15 of the 19 patients in which tissue and paired blood were collected at the same time point, 80% of the variants detected in tissue were also detected in the paired cfDNA. Higher concordance between tissue and cfDNA was found for variants with higher allele fraction in tissue (AFtissue ≥ 5%). Furthermore, 86% of the variants detected in cfDNA were also detected in paired tissue. Our study suggests that the genetic profile measured in blood cfDNA is complementary to that of tumor tissue in IBC patients.


Genes ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1047 ◽  
Author(s):  
Lama Jaffal ◽  
Wissam H Joumaa ◽  
Alexandre Assi ◽  
Charles Helou ◽  
George Cherfan ◽  
...  

Aim: To identify disease-causing mutations in four Lebanese families: three families with Bardet–Biedl and one family with Usher syndrome (BBS and USH respectively), using next generation sequencing (NGS). Methods: We applied targeted NGS in two families and whole exome sequencing (WES) in two other families. Pathogenicity of candidate mutations was evaluated according to frequency, conservation, in silico prediction tools, segregation with disease, and compatibility with inheritance pattern. The presence of pathogenic variants was confirmed via Sanger sequencing followed by segregation analysis. Results: Most likely disease-causing mutations were identified in all included patients. In BBS patients, we found (M1): c.2258A > T, p. (Glu753Val) in BBS9, (M2): c.68T > C; p. (Leu23Pro) in ARL6, (M3): c.265_266delTT; p. (Leu89Valfs*11) and (M4): c.880T > G; p. (Tyr294Asp) in BBS12. A previously known variant (M5): c.551A > G; p. (Asp184Ser) was also detected in BBS5. In the USH patient, we found (M6): c.188A > C, p. (Tyr63Ser) in CLRN1. M2, M3, M4, and M6 were novel. All of the candidate mutations were shown to be likely disease-causing through our bioinformatic analysis. They also segregated with the corresponding phenotype in available family members. Conclusion: This study expanded the mutational spectrum and showed the genetic diversity of BBS and USH. It also spotlighted the efficiency of NGS techniques in revealing mutations underlying clinically and genetically heterogeneous disorders.


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2433-2433 ◽  
Author(s):  
Archana M Agarwal ◽  
N. Scott Reading ◽  
Kimberly Frizzell ◽  
Wei Shen ◽  
Shelly Sorrells ◽  
...  

Abstract Hereditary hemolytic anemias are a heterogeneous group of disorders with consequences ranging from non-anemic hemolysis to severe life-threatening anemia. However, the late morbidity in patients without transfusions is often underappreciated because of erythropoietic compensatory stimulation inducing hematopoiesis by erythroferrone/hepcidin axis. Principal causes of hereditary hemolytic anemias are germline mutations of red cell cytoskeleton (e.g. hereditary spherocytosis and elliptocytosis/pyropoikilocytosis) or enzyme deficiencies (e.g. Glucose 6 phosphate dehydrogenase deficiency and pyruvate kinase deficiency). Routine morphological and biochemical analysis may be inconclusive and misleading particularly in transfusion-dependent infants and children. Molecular studies have not been extensively used to diagnose these disorders due to the complex genetic nature of these disorders, and multi-gene disorders. In these cases, patients may undergo multiple rounds of single gene testing, which can be very costly and time consuming. The advent of next generation sequencing (NGS) methods in the clinical laboratory has made diagnosing complex genetic disorders feasible. Our diagnostic panel includes 28 genes encoding cytoskeletal proteins and enzymes, and covers the complete coding region, splice site junctions, and, where appropriate, deep intronic or regulatory regions. Targeted gene capture and library construction for next-generation sequencing (NGS) was performed using Sure Select kit (Agilent Technologies, Santa Clara, USA). Prior to sequencing on the Illumina Next Seq, (Illumina Inc) instrument, indexed samples are quantified using qPCR and then pooled. Samples were sequenced using 2x150 paired end sequencing. We now report the first 68 patients evaluated using our NGS panel. The age of the patients ranged from newborn to 62 years. These patients presented with symptoms ranging from mild lifelong anemia to severe hemolytic anemia with extreme hyperbilirubinemia. Genetic variants were classified using the American College of Medical Genetics (ACMG) guidelines. We identified pathogenic variants in 11 patients and likely pathogenic variants in 12 others, the majority of these were novel. Many variants with unknown significance were also identified that could potentially contribute to disease. The most commonly mutated genes were SPTB and SPTA1, encoding spectrin subunits. Some complex interactions were uncovered i.e. SPTA1 mutations along with alpha LELY leading to hereditary pyropoikilocytosis; Spectrin variants along with Gilbert syndrome causing severe hyperbilirubinemia in neonates; and Spectrin variants in combination with PKLR and G6PD variants. Our results demonstrate that many patients with hemolytic anemia harbor complex combinations of known and novel mutations in RBC cytoskeleton/enzyme genes, but their clinical significance is further augmented by polymorphisms of UGT1A1 gene contributing to severe neonatal hyperbilirubinemia and its consequences. To conclude, next-generation sequencing provides a cost-effective and relatively rapid approach to molecular diagnosis, especially in instances where traditional testing failed. We have used this technology successfully to determine the molecular causes of hemolytic anemia in many cases with no prior family history. Disclosures Yaish: Octapharma: Other: Study investigator.


Author(s):  
Débora Cabral de Carvalho Corrêa ◽  
Francine Tesser-Gamba ◽  
Nasjla da Silva ◽  
Andrea Capellano ◽  
Maria Teresa Alves ◽  
...  

Background Congenital GBM (cGBM), presenting prenatally or within the first months of life, is among the rarest type of congenital brain tumor, with approximately 120 cases reported. Due to its infrequent occurrence, few studies have focused on the molecular and genetic aspects of this tumor, and the mutational events involved in the pathogenesis and progression of cGBM still remains poorly understood. This study aimed to investigate molecular alterations, with a potential prognostic marker and therapeutic target in cGBM using the next-generation sequencing (NGS) strategy. Methods We selected seven tumor samples from patients diagnosed with cGBM and treated at Pediatric Oncology Institute-GRAACC/UNIFESP. NGS was performed to identify somatic genetic variants in tumor samples using the Oncomine Childhood Cancer Research Assay panel, from ThermoFisher Scientific, designed specifically for pediatric neoplasms. Results Of all seven patients analyzed, three patients exhibited tumors with genetic variants, which include two pathogenic variants in NF1 and SUZ12 genes that have not been reported in cGBM yet, an increase in the number of copies of ALK gene, and two gene fusions, PPP1CB-ALK and TPM3-NTRK1. Also, none of the cases showed variants in H3F3A, TP53 and ATRX genes, alterations which are frequently seen in pediatric and adolescent GBM. Conclusions Our results suggest that cGBM may comprise a unique tumor entity and alterations in ALK and NTRK genes provide a potential target for therapy. Therefore, identification of genetic variants in cGBM is highly relevant in order to define prognosis and therapeutic strategies.


2021 ◽  
Vol 7 (6) ◽  
pp. e641
Author(s):  
Laura Canafoglia ◽  
Silvana Franceschetti ◽  
Antonio Gambardella ◽  
Pasquale Striano ◽  
Anna Teresa Giallonardo ◽  
...  

Background and ObjectivesTo assess the current diagnostic yield of genetic testing for the progressive myoclonus epilepsies (PMEs) of an Italian series described in 2014 where Unverricht-Lundborg and Lafora diseases accounted for ∼50% of the cohort.MethodsOf 47/165 unrelated patients with PME of indeterminate genetic origin, 38 underwent new molecular evaluations. Various next-generation sequencing (NGS) techniques were applied including gene panel analysis (n = 7) and/or whole-exome sequencing (WES) (WES singleton n = 29, WES trio n = 7, and WES sibling n = 4). In 1 family, homozygosity mapping was followed by targeted NGS. Clinically, the patients were grouped in 4 phenotypic categories: “Unverricht-Lundborg disease-like PME,” “late-onset PME,” “PME plus developmental delay,” and “PME plus dementia.”ResultsSixteen of 38 (42%) unrelated patients reached a positive diagnosis, increasing the overall proportion of solved families in the total series from 72% to 82%. Likely pathogenic variants were identified in NEU1 (2 families), CERS1 (1 family), and in 13 nonfamilial patients in KCNC1 (3), DHDDS (3), SACS, CACNA2D2, STUB1, AFG3L2, CLN6, NAXE, and CHD2. Across the different phenotypic categories, the diagnostic rate was similar, and the same gene could be found in different phenotypic categories.DiscussionThe application of NGS technology to unsolved patients with PME has revealed a collection of very rare genetic causes. Pathogenic variants were detected in both established PME genes and in genes not previously associated with PME, but with progressive ataxia or with developmental encephalopathies. With a diagnostic yield >80%, PME is one of the best genetically defined epilepsy syndromes.


Cancers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1364 ◽  
Author(s):  
Diego Carbonell ◽  
Julia Suárez-González ◽  
María Chicano ◽  
Cristina Andrés-Zayas ◽  
Juan Carlos Triviño ◽  
...  

Molecular diagnosis of myeloid neoplasms (MN) is based on the detection of multiple genetic alterations using various techniques. Next-generation sequencing (NGS) has been proved as a useful method for analyzing many genes simultaneously. In this context, we analyzed diagnostic samples from 121 patients affected by MN and ten relapse samples from a subset of acute myeloid leukemia patients using two enrichment-capture NGS gene panels. Pathogenicity classification of variants was enhanced by the development and application of a custom onco-hematology score. A total of 278 pathogenic variants were detected in 84% of patients. For structural alterations, 82% of those identified by cytogenetics were detected by NGS, 25 of 31 copy number variants and three out of three translocations. The detection of variants using NGS changed the diagnosis of seven patients and the prognosis of 15 patients and enabled us to identify 44 suitable candidates for clinical trials. Regarding AML, six of the ten relapsed patients lost or gained variants, comparing with diagnostic samples. In conclusion, the use of NGS panels in MN improves genetic characterization of the disease compared with conventional methods, thus demonstrating its potential clinical utility in routine clinical testing. This approach leads to better-adjusted treatments for each patient.


2018 ◽  
Vol 31 (12) ◽  
pp. 1295-1304 ◽  
Author(s):  
Taha R. Özdemir ◽  
Özgür Kırbıyık ◽  
Bumin N. Dündar ◽  
Ayhan Abacı ◽  
Özge Ö. Kaya ◽  
...  

Abstract Background Maturity-onset diabetes of the young (MODY) is a common form of monogenic diabetes. Fourteen genes have been identified, each leading to cause a different type of MODY. The aims of this study were to reveal both known and novel variants in MODY genes in patients with MODY using targeted next generation sequencing (NGS) and to present the genotype-phenotype correlations. Methods Mutation analysis of MODY genes (GCK, HNF1A, HNF4A, HNF1B, ABCC8, INS and KCNJ11) was performed using targeted NGS in 106 patients with a clinical diagnosis of MODY. The variants were evaluated according to American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines recommendations. Results A total of 18 (17%) variants were revealed among all patients. Seven variants in GCK, six in HNF4A, four in HNF1A and one in ABCC8 genes were found. Eight of them were previously published and 10 of them were assessed as novel pathogenic or likely pathogenic variants. Conclusions While the most frequent mutations are found in the HNF1A gene in the literature, most of the variants were found in the GCK gene in our patient group using the NGS method, which allows simultaneous analysis of multiple genes in a single panel.


Sign in / Sign up

Export Citation Format

Share Document