Category Archives: Best practices in genetic analysis

Secondary Analysis 2.0 – Part IV

         August 15, 2017
Detection of CNVs

Examples of CNV Calling What do CNV calls actually look like? What are some of the key metrics to determine an event? Part IV of the Secondary Analysis 2.0 blog series will answer these questions by walking through some examples of how our CNV caller, VS-CNV, identifies CNVs. Golden Helix integrates multiple metrics to determine if a CNV event is… Read more »

Secondary Analysis 2.0 – Part III

         August 8, 2017
Detection of CNVs

Detection of CNVs in NGS Data Our Secondary Analysis 2.0 blog series continues with Part III: Detection of CNVs in NGS Data. We will give you an overview of some design principles of a CNV analytics framework for next-gen sequencing data. There are a number of different approaches to CNV detection. The published algorithms share common strategies to solve the… Read more »

Secondary Analysis 2.0 – Part II

         August 1, 2017
Detection of CNVs

In this blog series, I will discuss the architecture of a state of the art secondary pipeline that is able to detect single nucleotide variations (SNV) and copy number variations (CNV) in one test leveraging next-gen sequencing. In Part I, we reviewed genetic variation in humans in general and looked at the key components of a systems architecture supporting this… Read more »

Secondary Analysis 2.0 – Part I

         July 18, 2017
Detection of CNVs

Human genetic variation makes us unique. On average, humans are to 99.9% similar to each other. Understanding in detail what the nature of the difference in our genetic make-up is all about allows us to assess health risks, and eventually enables Precision Medicine as we determine treatment choices. Furthermore, it enables scientists to better understand ancient human migrations. It gives… Read more »

Paying Attention to the Quality Fields in ExAC: A Case Study

         March 7, 2017

In the past couple of weeks, the topic of the Filter and Quality fields in the popular ExAC population catalog has come up a number of times. It turns out that unlike the 1000 Genomes project, which decided to very heavily filter their variant list to only contain variants they consider high quality, ExAC chose to include more dubious variants… Read more »

PhoRank in SVS: Gene Ranking for Your Research Genotypes

         February 9, 2017
gene ranking

Since we released our Phenotype Gene Ranking algorithm in VarSeq, it has become a staple of the way people conduct their analysis. It allows for a combination of filtering with ranking to prioritize follow-up interpretations of analysis results. Our PhoRank algorithm will be available in our upcoming SVS release to also aid in the numerous research workflows performed on SNPs… Read more »

GWAS 3.0

         February 7, 2017
GWAS eBook

Genome-wide association study (GWAS) technology has been a primary method for identifying the genes responsible for diseases and other traits for the past ten years. GWAS continues to be highly relevant as a scientific method. Over 2000 human GWAS reports now appear in scientific journals. In fact, we see its adoption increasing beyond the human-centric research into the world of… Read more »

ExAC CNVs: The First Large Scale Public Exome CNV Variant Set

         December 8, 2016
ExAC CNVs

ExAC CNVs were released publicly with a recent publication, providing the full set of rare CNVs called on ~60K human exomes. While there are many public CNV databases out there, this is the first one that was derived from exome data, and thus includes both extremely rare and very small CNV events. With the recent release of Golden Helix’s CNV calling… Read more »

WEBCAST: CNV Analysis with VarSeq

         November 22, 2016

December’s webcast will provide the Golden Helix community with a more in-depth look at CNV analysis in VarSeq. On December 7th, Dr. Nathan Fortier will discuss the challenges and metrics surrounding CNV detection and then demonstrate VarSeq’s new capability from VCF to clinical report.  Wednesday, December 7th @ 12:00 PM, EST Numerous studies have documented the role of Copy Number Variations (CNVs)… Read more »

Genotype Imputation and Phasing now in SNP & Variation Suite

         November 8, 2016
Genotype Imputation

One of the tools at the top of the toolbox for researchers working with microarray data is genotype imputation. Genotype imputation is the process of inferring the genotype of one or more markers based on the correlation pattern (aka linkage disequilibrium or LD) of the surrounding markers for which genotypes are known. We have now integrated a natively ported version of BEAGLE into Golden… Read more »

Using GWAS to investigate neurodevelopmental disorders

         October 18, 2016
Sergey Kornilov

Dr. Sergey Kornilov, a Duncan Scholar in Molecular and Human Genetics at Baylor College of Medicine, combines his broad psychology background with genetics to research the genetic basis of neurodevelopmental disorders with a unique dual perspective. Neuro-developmental disorders, for example, those of the spoken and written language, affect many worldwide – up to 10% of preschool children. In most cases, these… Read more »

Why Call CNVs: Getting More from your NGS Data

         October 11, 2016
CNV Call

Copy Number Variants have been important to clinical genetics for quite a while now. So, what has made now the right time to be looking at calling CNVs from NGS data? Well, there are a number of good reasons. The dominant one is simply that the NGS data you are already creating for calling variants can be used in many cases… Read more »

FAQ: Creating Repeatable Clinical Workflows

         August 18, 2016
Repeatable clinical workflows

Question: Now that I’ve added annotation sources for my sample, filtered down to a list of interesting variants, flagged those variants and generated a clinical report, can I save or copy the annotation sources and filters for use on another sample? Short Answer: Yes! Long Answer: VarSeq was created with ease and efficiency in mind. In VarSeq, once you’ve defined… Read more »

Compute Kinship Matrices & GBLUP on Very Large Sample Sets

         August 2, 2016
Binary Data

Now available in SVS! Increasingly important in the analysis of the genotype to phenotype relationship is accurately accounting for the relatedness of samples. This is especially important to model correctly in plant and animal populations where man-directed breeding shapes the relationship structure. Along with trait association, one of the high-value use cases for genotyping animals and plants is to estimate… Read more »

Our 5 Most Watched Webcasts

         July 21, 2016
5 Most Watched Webcasts

Every month hundreds of clinicians and researchers access the variety of free resources on the Golden Helix website. Our resource library hosts eBooks, webcasts and tutorials to keep the community apprised of new methods, informed on best practices and to help our customers get the most out of their software purchase. Here is a list of the 5 most watched webcasts… Read more »

Variant Normalization: Underappreciated Critical Infrastructure

         July 7, 2016
Variant Normalization

Variant Normalization: Underappreciated Critical Infrastructure It may surprise you to learn that every variant in the human genome has an infinite number of representations! Of course, although true, I’m being a bit hyperbolic to prove a point. Even seemingly simple mutations like single letter substitutions are legitimately represented differently in the local context of other mutations that can be described… Read more »

Bridging Two Worlds: Lifting Over Your Variants to GRCh38

         June 7, 2016
GRCh38

When the new human reference genome was released over two years ago, it was hailed as a significant step forward for next generation sequencing. Compared to GRCh37, the new GRCH38 reference assembly fixed gaps, repaired incorrect sequences and offered access to sections of the genome that had been previously unaccounted for. Despite these improvements, adoption of the new assembly has… Read more »

CADD Scores: Rank and Filter in Harmony!

         May 19, 2016
VSClinical algorithm

There used to be much energy expended at conferences, bioinformatics forums and even publications about what was the better strategy for interpreting variants of clinical significance: Rule-based filtering and classification mechanisms or rank-based prioritization through all-encompassing “pathogenicity” scores. Both have shown to be effective. Rule-based systems, as exemplified in this filtering diagram in Baylor’s ground-breaking paper on clinical whole-exome sequencing… Read more »

Solving the Eigenvalue Decomposition Problem for Large N

         May 5, 2016
Eigenvalue Decomposition

Solving the Eigenvalue Decomposition Problem for Large Sample Sizes Since our introduction of the mixed model methods in SVS, along with GBLUP, we have been very pleased to see it used by a number of customers working with human and agri-genomic data. As these customers have grown their genomics programs, the number of samples they have for a given analysis… Read more »

N-of-One Integration comes to VSReports

         April 28, 2016

Submit directly to N-of-One from VarSeq If you or your lab uses N-of-One solutions for clinical annotations, here’s some good news: You can now submit directly to N-of-One from VarSeq! N-of-One’s set of preferred transcripts may differ from those outputted by our algorithms in VarSeq, so our solution was built with that in mind. Our slick, easy to use, and… Read more »