scholarly journals Accuracy of analysis of cfDNA for detection of single nucleotide variants and copy number variants in breast cancer

BMC Cancer ◽  
2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Xin Yang ◽  
Kuo Zhang ◽  
Caiji Zhang ◽  
Rongxue Peng ◽  
Chengming Sun
Keyword(s):  
Breast Cancer ◽  
Copy Number ◽  
Copy Number Variants ◽  
Single Nucleotide Variants ◽  
Single Nucleotide

scholarly journals An integrative approach to investigate the respective roles of single-nucleotide variants and copy-number variants in Attention-Deficit/Hyperactivity Disorder

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Leandro de Araújo Lima ◽  
Ana Cecília Feio-dos-Santos ◽  
Sintia Iole Belangero ◽  
Ary Gadelha ◽  
Rodrigo Affonseca Bressan ◽  
...  
Keyword(s):  
Attention Deficit Hyperactivity Disorder ◽  
Attention Deficit ◽  
Copy Number ◽  
De Novo ◽  
Copy Number Variants ◽  
Integrative Approach ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Hyperactivity Disorder ◽  
New Genes

Abstract Many studies have attempted to investigate the genetic susceptibility of Attention-Deficit/Hyperactivity Disorder (ADHD), but without much success. The present study aimed to analyze both single-nucleotide and copy-number variants contributing to the genetic architecture of ADHD. We generated exome data from 30 Brazilian trios with sporadic ADHD. We also analyzed a Brazilian sample of 503 children/adolescent controls from a High Risk Cohort Study for the Development of Childhood Psychiatric Disorders, and also previously published results of five CNV studies and one GWAS meta-analysis of ADHD involving children/adolescents. The results from the Brazilian trios showed that cases with de novo SNVs tend not to have de novo CNVs and vice-versa. Although the sample size is small, we could also see that various comorbidities are more frequent in cases with only inherited variants. Moreover, using only genes expressed in brain, we constructed two “in silico” protein-protein interaction networks, one with genes from any analysis, and other with genes with hits in two analyses. Topological and functional analyses of genes in this network uncovered genes related to synapse, cell adhesion, glutamatergic and serotoninergic pathways, both confirming findings of previous studies and capturing new genes and genetic variants in these pathways.

Basic principles of genetic disease

ESC CardioMed ◽  
2018 ◽  
pp. 669-671
Author(s):  
Eric Schulze-Bahr
Keyword(s):  
Genetic Disease ◽  
Copy Number ◽  
Copy Number Variants ◽  
Single Nucleotide Variants ◽  
Individual Genome ◽  
Base Pairs ◽  
Single Nucleotide ◽  
Basic Principles ◽  
Bona Fide ◽  
Genomic Regions

The human genome consists of approximately 3 billion (3 × 109) base pairs of DNA (around 20,000 genes), organized as 23 chromosomes (diploid parental set), and a small mitochondrial genome (37 genes, including 13 proteins; 16,589 base pairs) of maternal origin. Most human genetic variation is natural, that is, common or rare (minor allele frequency >0.1%) and does not cause disease—apart from every true disease-causing (bona fide) mutation each individual genome harbours more than 3.5 million single nucleotide variants (including >10,000 non-synonymous changes causing amino acid substitutions) and 200–300 large structural or copy number variants (insertions/deletions, up to several thousands of base-pairs) that are non-disease-causing variations and scattered throughout coding and non-coding genomic regions.

Genetics of Schizophrenia and Bipolar Disorder

2017 ◽  
Author(s):  
Alexander Charney ◽  
Pamela Sklar
Keyword(s):  
Bipolar Disorder ◽  
Copy Number ◽  
Psychotic Disorders ◽  
Copy Number Variants ◽  
Nucleotide Polymorphisms ◽  
Common Variants ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Number Variation

Schizophrenia and bipolar disorder are the classic psychotic disorders. Both diseases are strongly familial, but have proven recalcitrant to genetic methodologies for identifying the etiology until recently. There is now convincing genetic evidence that indicates a contribution of many DNA changes to the risk of becoming ill. For schizophrenia, there are large contributions of rare copy number variants and common single nucleotide variants, with an overall highly polygenic genetic architecture. For bipolar disorder, the role of copy number variation appears to be much less pronounced. Specific common single nucleotide polymorphisms are associated, and there is evidence for polygenicity. Several surprises have emerged from the genetic data that indicate there is significantly more molecular overlap in copy number variants between autism and schizophrenia, and in common variants between schizophrenia and bipolar disorder.

Circulating cell-free DNA (ctDNA) assessments before, during, and after neoadjuvant therapy (NAC) in nonmetastatic inflammatory breast cancer (IBC).

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e12113-e12113
Author(s):  
Carolyn S. Hall ◽  
Salyna Meas ◽  
Vanessa Nicole Sarli ◽  
Anthony Lucci
Keyword(s):  
Breast Cancer ◽  
Pathologic Complete Response ◽  
Copy Number Variants ◽  
Residual Tumor ◽  
Complete Response ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Cell Free Dna ◽  
Free Dna ◽  
Circulating Cell Free Dna

e12113 Background: : IBC is a rare and aggressive subtype of breast cancer. A significant number of IBC patients who achieve pathologic complete response (no residual tumor in breast and axillary nodes, pCR) relapse after NAC. We hypothesized that circulating cell-free DNA (ctDNA) identified in blood before, during, and after NAC would identify novel ctDNA targets. Methods: Plasma ctDNA was extracted from 43 non-metastatic IBC patients (IRB: LAB04-0698) pre, mid, and post-NAC. The Oncomine Pan Cancer ctDNA Assay (ThermoFisher) was used for library preparation, and high throughput next generation sequencing was performed on a GeneStudio S5XL System (ThermoFisher), following manufacturer’s directions. ThermoFisher Ion Reporter 5.10 Software was used to analyze single nucleotide variants (SNVs), and copy number variants (CNVs). Results: Seventeen patients had pre-NAC ctDNA assessments; 7/17 (41%) had PIK3CA SNVs; 5/7 also had MYC or FGFR2 CNVs. Five of 17 (29%) had TP53 SNVs; 2/5 also had FGFR2 CNVs. Ten patients had mid-NAC ctDNA assessments; 9/10 (90%) had PIK3CA SNVs; 5/9 also had FGFR2 CNVs, 2/9 had FGFR2 and FGFR3 CNVs, 2/9 also had TP53 SNVs, 1/9 had FGFR2 and ERB2 CNVs. Thirty-one patients had post-NAC ctDNA assessments; 5/31 (16%) had PIK3CA SNVs; 2/5 had FGFR2 CNVs, 1/5 also had a TP53 mutation and an FGFR2 CNV, 1/5 had FGFR2 CNV, and FGFR3 CNV. Six of 31 (19%) had TP53 SNVs, 1/6 had CCND1 CNVs, no CNVs were detected in 6 patients with TP53 SNVs. Six of 31 (19%) had MAP2K1 SNVs. Three of 31 (10%) had MET SNVs; 1/3 had CCND3 CNVs, no CNVs were detected in 2 patients with MET SNVs. No SNVs or CNVs were detected in 10/31 (32%) of patients post NAC. Conclusions: ctDNA assessments before, during, and after NAC identified novel targets that could be tested in future adjuvant therapies trials in IBC patients who remain at high risk for relapse.

Genetics of Schizophrenia and Bipolar Disorder

2013 ◽  
pp. 232-246 ◽  
Author(s):  
Pamela Sklar
Keyword(s):  
Bipolar Disorder ◽  
Copy Number ◽  
Psychotic Disorders ◽  
De Novo ◽  
Copy Number Variants ◽  
Nucleotide Polymorphisms ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Sequencing Studies ◽  
Number Variation

Schizophrenia and bipolar disorder are the classic psychotic disorders. Both diseases are strongly familial, but have proven recalcitrant to genetic methodologies for identifying the etiology until recently. The explosion of strong and convincing genetic evidence indicates a contribution of many DNA changes to the risk of becoming ill. For schizophrenia, there are large contributions of rare copy number variants and common single nucleotide variants, with an overall highly polygenic genetic architecture. There is a role for rare single nucleotide variation as well as de novo genetic variation being pointed to in new sequencing studies, but their overall contribution to risk is less clear. For bipolar disorder, the role of copy number variation appears to be much less pronounced. Specific common single nucleotide polymorphisms are associated, there is evidence for polygenicity and as yet no deep sequencing surveys have been published. Several intriguing biological pathways are suggested by these genetic findings related to microRNAs and calcium channel signaling. Several surprises have emerged from the genetic data that indicate there is significantly more molecular overlap in copy number variants between autism and schizophrenia, and in common variants between schizophrenia and bipolar disorder. Translating these results into biological and etiological understanding has not yet advanced, and will likely only do so when experimental methods are developed than can address the large numbers of genes and variants within them that, along with environmental and stochastic effects, result in the development of disease for a particular person.

scholarly journals Genome sequencing identifies rare tandem repeat expansions and copy number variants in Lennox–Gastaut syndrome

2021 ◽  
Vol 3 (3) ◽  
Author(s):  
Farah Qaiser ◽  
Tara Sadoway ◽  
Yue Yin ◽  
Quratulain Zulfiqar Ali ◽  
Charlotte M Nguyen ◽  
...  
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Tandem Repeat ◽  
Copy Number ◽  
Copy Number Variants ◽  
Spinocerebellar Ataxia Type ◽  
Whole Genome ◽  
Single Nucleotide Variants ◽  
Single Nucleotide ◽  
Repeat Expansions

Abstract Epilepsies are a group of common neurological disorders with a substantial genetic basis. Despite this, the molecular diagnosis of epilepsies remains challenging due to its heterogeneity. Studies utilizing whole-genome sequencing may provide additional insights into genetic causes of epilepsies of unknown aetiology. Whole-genome sequencing was used to evaluate a cohort of adults with unexplained developmental and epileptic encephalopathies (n = 30), for whom prior genetic tests, including whole-exome sequencing in some cases, were negative or inconclusive. Rare single nucleotide variants, insertions/deletions, copy number variants and tandem repeat expansions were analysed. Seven pathogenic or likely pathogenic single nucleotide variants, and two pathogenic deleterious copy number variants were identified in nine patients (32.1% of the cohort). One of the copy number variants, identified in a patient with Lennox–Gastaut syndrome, was too small to be detected by chromosomal microarray techniques. We also identified two tandem repeat expansions with clinical implications in two other patients with Lennox–Gastaut syndrome: a CGG repeat expansion in the 5′untranslated region of DIP2B, and a CTG expansion in ATXN8OS (previously implicated in spinocerebellar ataxia type 8). Three patients had KCNA2 pathogenic variants. One of them died of sudden unexpected death in epilepsy. The other two patients had, in addition to a KCNA2 variant, a second de novo variant impacting potential epilepsy-relevant genes (KCNIP4 and UBR5). Overall, whole-genome sequencing provided a genetic explanation in 32.1% of the total cohort. This is also the first report of coding and non-coding tandem repeat expansions identified in patients with Lennox–Gastaut syndrome. This study demonstrates that using whole-genome sequencing, the examination of multiple types of rare genetic variation, including those found in the non-coding region of the genome, can help resolve unexplained epilepsies.

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