Author Archives: Nathan Fortier

About Nathan Fortier

Nathan Fortier, Ph.D, Director of Research for Golden Helix, joined the development team in June of 2014. Nathan obtained his Bachelor’s degree in Software Engineering from Montana Tech University in May 2011, received a Master’s degree in Computer Science from Montana State University in May 2014, and received his Ph.D. in Computer Science from Montana State University in May 2015. Nathan works on data curation, script development, and product code. When not working, Nathan enjoys hiking and playing music.

Reviewing Clinical Studies for Novel Splice Variants in VSClinical

         October 12, 2021
DNA spliced site

In order to thoroughly assess a variant’s pathogenicity, it is important to take into account the variant’s effect on splicing. While the interpretation of variants that disrupt the pairs of bases at the beginning of a splice site is fairly straightforward, variants resulting in the introduction of a novel splice site are more difficult to interpret. In this blog post,… Read more »

Manage gene lists across projects with VarSeq and VSClinical

         August 18, 2021

Clinical labs often maintain gene panels, which are lists of genes with evidence of disease association. These panels are used to prioritize variants and limit interpretations to a predefined set of test-specific genes. In general, gene panels should be stored independently of any specific project or interpretation, as it is common for an individual gene panel to be generally applicable… Read more »

Leveraging expert-curated variant interpretations using VSClinical

         July 27, 2021
Clinical Genome Resource

This blog post will cover an exciting new VSClinical feature in the upcoming VarSeq release. The ACMG Previously Interpreted Variants feature allows users to integrate databases of expert-curated variant interpretations into their VSClinical workflows. These data sources store variant-level interpretation data, including the classification, associated disorders, interpretation text, and scored criteria for each variant, along with notes providing a justification… Read more »

Highlights from our PhoRank 2.0 Webcast

         June 10, 2021

Thank you to those who attended our recent webcast, “PhoRank 2.0: Improved Phenotype-Based Gene Ranking in VarSeq”. For those who could not attend, you can find a link to the recording here. This webcast covered upcoming improvements to the PhoRank phenotype-based gene ranking algorithm based on literature published in the years since the algorithm’s development. The PhoRank Algorithm When performing… Read more »

Webcast Recap: High Precision Exome CNV Detection with VS-CNV

         May 7, 2021

Thank you to those who attended the recent webcast, “High Precision Exome CNV Detection with VS-CNV”. For those who could not attend but wish to watch, here is a link to the recording. This webcast delved into the complex world of CNV calling for whole-exome samples, which presents unique challenges that require specific considerations and strategies. Over the past several months,… Read more »

VarSeq Update: Support for the Interpretation of Non-coding and Splice Site Variants

         April 15, 2021
Splice site

While VarSeq has always had excellent support for variant interpretation and analysis, we continue to find new edge cases in the clinical literature that improve our interpretation capabilities. In this blog, we will be covering some of the new improvements in VarSeq to support the interpretation of non-coding and splice site variants. Transcript Annotation Improvements Let’s start by covering some… Read more »

Updates on Splice Site Analysis

         February 2, 2021

Our latest VarSeq release is one of the largest we’ve ever had, boasting an extensive list of new features and improvements. As part of this release, we have dramatically expanded our support for splice site analysis. This includes improvements to our novel splice site algorithm and support for splice site effect prediction along with several other small improvements. Novel Splice… Read more »

Exporting Genes as Exon Regions in VS-CNV

         June 16, 2020
CNV Het Deletion

We have had many customers come to us over the years with a simple problem: they have BAM files for whole exome or gene panel data and would like to call CNVs using VarSeq’s powerful CNV calling capabilities, but they don’t have a bed file defining the target regions for their samples. To address this problem, we have developed a… Read more »

Recent Webcast: Evaluating Oncogenicity in VSClinical

         June 11, 2020

Abstract Before assessing the clinical significance of a somatic mutation, one must determine if the mutation is likely to be a driver mutation (i.e. a mutation that provides a selective growth advantage, thereby promoting cancer development). To aid clinicians in this process, VSClinical provides an oncogenicity scoring system, which uses a variety of metrics to classify a given somatic mutation… Read more »

Detecting de Novo Copy Number Inheritance and Family Segregations

         April 23, 2020

In trio workflows, one of the most important factors in scoring a variant is understanding how that variant is inherited from the parents. Likewise, when looking at extended families, the segregation, or presence of the variant among the affected versus unaffected individuals provides evidence for its pathogenicity for a given phenotype or disease. Given the nature of Copy Number Variants… Read more »

Introducing Drugs & Trials for Cancer Diagnostics

         January 23, 2020

When interpreting a variant using the AMP/ASCO guidelines for somatic variant interpretation, clinicians must determine whether the variant can be considered a biomarker that affects clinical care by predicting sensitivity, resistance, or toxicity to a specific therapy. Such a determination requires the investigation of multiple evidence sources, including clinical trials, FDA approved therapies and peer-reviewed studies. Unfortunately, strong evidence linking… Read more »

Oncogenicity Scoring in VSClinical

         October 1, 2019
Oncogenicity Scoring in VSClinical

Before examining the clinical evidence associated with a specific mutation, a clinician must establish that the variant is likely to be a driver mutation which generates functional changes that enhance tumor cell proliferation. Our recent blog series “Following the AMP Guidelines with VSClinical” briefly mentioned how the oncogenicity scoring system in VSClinical could be used to automate and assist the… Read more »

Considerations When Calling CNVs on Shallow Whole Genomes

         December 20, 2018
CNV Annotations

We are happy to announce that our latest version of SVS includes the ability to call CNVs on low read depth Whole Genome Sequencing (WGS) data. Designed for calling large cytogenetic events, this algorithm can detect chromosomal aneuploidy events and other large events spanning one or more bands of a chromosome from genomes with average coverage as low as 0.05x…. Read more »

Functional Predictions & Conservation Scores in VSClinical

         May 17, 2018

In our previous webcast, we discussed the splice site algorithms for clinical genomics within VSClinical. We took it a step further in yesterday’s webcast and looked at the functional predictions and conservation scores. We had a great turnout for this event with lots of great questions from the attendees. I’d like to recap our Q&A for anyone else who might… Read more »

Revisiting the Five Splice Site Algorithms used in Clinical Genetics

         January 16, 2018

Interpretation of variants in accordance with the ACMG guidelines requires that variants near canonical splice boundaries be evaluated for their potential to disrupt gene splicing [1]. The five most common tools for splice site detection are NNSplice, MaxEntScan, GeneSplicer, HumanSplicingFinder, and SpliceSiteFinder-like. Because these algorithms have been made easily accessible in the bioinformatics tool Alamut, they have been canonized for… Read more »

Calling Cytogenetic CNVs from Shallow Whole Genomes

         June 21, 2017
low read depth

Low read depth? Great! We are excited to introduce our new CNV calling algorithm for low and ultra-low read depth Whole Genome Sequencing (WGS) data. This algorithm is designed to call large cytogenetic events with high confidence from low read depth whole genome data, with as few as one million aligned reads or 0.02x coverage. The low sequencing cost of… 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 »

New Plugin for Ion Torrent Server

         October 21, 2014

Golden Helix is proud to announce the release of the Golden Helix GenomeBrowse Plugin for Ion Torrent server. The new plug-in enables adding selected BAM files from Torrent Server reports directly into GenomeBrowse. The BAM files remain on the torrent server and are streamed from the server on demand using your credentials. This feature allows GenomeBrowse users to visualize genomic… Read more »