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What does a sequence alignment and variant call report look like?

Our sequence alignment and variant call reports are generated by a tool called Geneious Prime. We export a select list of variables including CDS, polymorphism types, codon change, amino acid change, and protein effect. There is a wealth of…
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What does an HLA report look like?

Our HLA reports are generated automatically by the GenDX NGSengine® software and includes information about HLA allele typing calls, allele ambiguities and relevant metadata. The exact set of loci displayed in an HLA report will depend on…
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How to perform an NCBI nucleotide BLAST search

We often use NCBI nucleotide Blast queries to identify DNA sequences derived from Next Generation Sequencing (NGS) runs.  This brief note describes how to use the NCBI Blast algorithm and website with NGS DNA datasets. Create an NCBI Account Before…
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HLA PIRCHE matching service

NGSengine can now export HLA typing results of an individual sample directly to the PIRCHE matching services website. This will facilitate laboratories to predict indirectly recognizable HLA epitopes for either hematopoietic stem cells or solid…
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What does “exon mismatch” mean in HLA reports?

If you see the identifier "exon mismatch" in some alleles in our HLA reports, there may be a good explanation for it.  We'll explain briefly here.   IMGT Database The IMGT HLA database is a standard reference library for determining…
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How to annotate a genome with Geneious

Geneious Annotations Geneious Prime includes genome annotation features and reports.  Annotation is often used to describe the structure and function of various genomic regions, such as genes, CDS's (coding sequences), exons, introns, 5'-…
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How to create Geneious variant call reports

Geneious Reports We have numerous clients who use Geneious for bioinformatics data analysis.  They use Geneious for sequence alignments of their sample datasets against reference genomes and for the interpretation of Geneious variant call…
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Microbiome reports with Kraken

We use a variety of data analysis tools such as OneCodex and Megan6 for quantifying and visualizing metagenomic sequencing datasets. Kraken2 is a popular taxonomic classification tool for metagenomic and microbiome sequencing results. The…
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Do you have a GenDx HLA publication list?

We vet our vendors carefully before using products in our sequencing workflows.  The Sequencing Center uses the GenDx libraries for NGS (Next Generation Sequencing)-based HLA typing.  The combination of substantial immunological research,…
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Geneious sequence alignment & variant calls workflow

Geneious Prime is one of many bioinformatics tools that we use to post-process sequencing datasets.  Geneious includes an extensive set of functions to perform sequence alignments of sample reads against reference genomes.  And it includes…
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How do you read HLA reports?

We deliver detailed HLA reports to clients immediately after their HLA sequencing runs are complete. The reports include information about HLA allele typing calls, allele ambiguities, and relevant metadata. HLA Loci The full set of HLA loci…
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Trimming Illumina adapter sequences

Adapter Sequences During the library preparation process, Illumina adapter sequences are annealed to sequencing reads.  The adapter sequences are required for attaching reads to flow cells and for attaching indexes to reads.  When sequencing…

What’s included in “basic bioinformatics”?

The Sequencing Center provides basic bioinformatics as an inclusive service with all genome sequencing projects. Here's what you can expect to receive with each type of project. Microbial Projects FASTQ Files: All microbial sequencing projects…
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What is de novo assembly?

De novo assembly is a method for constructing genomes from a large number of (short- or long-) DNA fragments, with no a priori knowledge of the correct sequence or order of those fragments. The terminology for de novo assembly is sometimes…
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What are unmapped reads?

Save Unmapped Reads One of the most common activities we perform is the sequence alignment of sequenced bacterial samples against known reference genomes.  The alignment process generates two types of output: mapped reads and unmapped reads.…
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How to find a reference genome

The goal of many sequencing projects is to identify polymorphisms and mutations in sequenced samples.  These often include SNP's, indels, chromosomal rearrangements, and various kinds of spontaneous or induced changes in nucleotide sequence. …
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What are HLA ambiguous alleles?

In our CareDx TruSight Assign HLA reports, ambiguous alleles are identified with a double dash (- -). For example, "- -:01:01" indicates an ambiguity in the first field, "01:- -:01" indicates an ambiguity in the second field, and "01:01:-…
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Can you explain HLA allele nomenclature?

The standardized HLA gene and allele nomenclature is managed by the WHO Nomenclature Committee for Factors of the HLA System.  A high-level summary of their nomenclature system is reproduced here for easy reference.  A thorough and detailed…
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How to read Geneious variant call reports

Reading Geneious Reports We often use Geneious to generate SNP/indel variant call reports.  A truncated report is available here.  (The number of SNP's/indels in a typical report can be quite large so we only show a few records in this example).   Report…

Can I use one of my sequenced samples as a reference genome?

We are often asked if clients can submit several samples at once for sequencing and then use one of the samples as a reference genome to compare against the remaining samples.  For example, clients may have a single control sample and several…