Small Variant Details¶
This page provides more detail about a specific variant. For details on how to use the classification card, and how this is saved in the history, see the recording interpretation page page.
Variant information¶
The variant information card contains basic information about the variant.
Key
# | Section | Description |
---|---|---|
1 | Variant coordinates | VCF format of the variant |
2 | Copy nomenclature button | Copies the variant coordinates in Alamut format |
3 | External links | Contains a link to IGV (for read depth investigation), and links to external databases and resources for the variant (DECIPHER, gnomAD, UCSC, VarSome and SpliceAI). |
4 | Header | Contains the same details as sections 1, 2, and 3, as well as the type of SNV,which remain visible upon scrolling. |
Gene information¶
The gene information card contains a tab for each gene that the variant is seen in. Clicking on each gene tab provides more information about that gene and its transcripts.
Key
# | Section | Description |
---|---|---|
1 | Gene name | Gene name |
2 | Gene colour | The gene is coloured green when it is green in the most recent PanelApp version, and that panel matches the GMS PanelApp panel applied to the patient (i.e. it is counterpart to the GMS version). Green gene status currently only applies to Tiered variants. |
3 | Gene ID | Ensembl gene ID |
Non-GMS PanelApp panels¶
This section displays the non-GMS PanelApp panels for the gene (including version and a link-out to the PanelApp page for the panel). For each panel, we see the gene rating (green, amber, red), and PanelApp's MOI for the gene. If there is no MOI recorded in PanelApp, then this will be displayed as Unknown. If the gene has been removed from the panel in the most recent version, then a '-' is displayed in the Gene status column, and the Gene MOI will be displayed as Unknown. If the gene is present in no non-GMS PanelApp panels, then None is displayed in place of all data.
PanelApp data is queried, per case, at the point of ingestion, thus it is the latest available at the point in time the patient was loaded into the New IB.
OMIM associated diseases¶
Displays any diseases associated with the gene in OMIM, as well as the gene-phenotype mode of inheritance, and a link-out to the OMIM page for each disease.
Where there is more than 1 associated disease the data will be displayed in a table, and pages of the table can be navigated between using the arrow buttons.
External links¶
Linkouts to external resources and databases for the gene (OMIM, PubMed, PanelApp, ClinGen).
Transcript information¶
Table containing details of transcripts for that gene which overlap the variant. A '-' in the table indicates that this data is not available for the transcript. Transcripts are ordered by the following priority:
- Most severe consequence
- Mane Select
- Mane Plus Clinical
- GENCODE Basic
Any transcripts that do not match the above criteria are displayed unordered.
Key
# | Section | Description |
---|---|---|
1 | Transcript / RefSeq Match | Ensembl transcript ID is provided for each transcript, and RefSeq NM number is provided for MANE transcripts. These provide linkouts to the respective transcript pages. RefSeq transcript IDs are only provided for MANE transcripts, as only these guarantee 100% sequence identity between the respective Ensembl and Refseq transcript IDs. If the transcript is MANE then a flag will be displayed (M for MANE Select and M+ for MANE Plus Clinical). If more than 5 transcripts exist, then these can be navigated through using the arrows at the bottom of the table |
2 | CDS change | The c. HGVS nomenclature for the CDS change |
3 | Protein change | The p. HGVS nomenclature for the protein change |
4 | Consequence | Predicted consequence types (SO terms) for the transcript. N.B. multiple consequences can be associated with the same transcript. If the consequence is the most severe, an S flag will be displayed |
5 | Protein ID (Ensembl ID) | Ensembl ID for the protein produced by the transcript |
6 | Entries per page | Number of transcripts to display in the table can be modified using this drop-down |
7 | Navigation arrows | Navigate through pages of the table using these buttons |
Population frequencies¶
The population frequencies card provides allele frequency details for all available studies for the variant, as annotated by Cellbase (Genomics England Annotation Service). A table is displayed per study. This could include: gnomAD mitochondrial (only visible for mitochondrial variants), gnomAD genomes, gnomAD exomes, and Genomics England internal studies. If the variant has a gnomAD allele frequency of 0 for a study subpopulation in gnomAD, then the row for that subpopulation will not be displayed in the table for that study. If the variant has no population data available for a single study, then No entries will be visible in the table for that study. If the variant has no population data available across all studies, then a message No entries for this variant in gnomAD or Genomics England internal database will be visible in place of the individual study data.
Where a variant has an allele frequency of more than 0 and less than 0.0001, this will be displayed as <0.0001. For any allele frequency of >0.0001, the exact value will be displayed.
To find out the versions of population datasets used for annotation, please visit the software and dataset versions section.
Key
# | Section | Description |
---|---|---|
1 | Tooltip | Provides additional information about the section |
2 | Max allele frequency | Maximum allele frequency across all studies. Click on the tooltip for higher granularity (allele count and allele number) |
3 | Study | Study which contains the subpopulation with the maximum allele frequency across all studies |
gnomAD exomes and genomes¶
These tables display gnomAD population frequency data for the variant, from the exomes and genomes population datasets.
Key
# | Section | Description |
---|---|---|
1 | Study name | Name of the study - gnomAD exomes or gnomAD genomes |
2 | Population | Data is provided by population within the study. Population is only visible where number of alt alleles > 0 |
3 | Alt allele frequency for the variant | Frequency of the variant within the population dataset |
4 | Number homozygous genotypes | Number of individuals within the population dataset that are homozygous for the variant |
5 | Number of alt alleles | Number of times the variant is observed within the population dataset |
6 | Allele number - total number of alleles | Total count of reference alleles and variant alleles observed in the population dataset for that variant |
gnomAD mitochondrial¶
If the variant is mitochondrial, this table displays gnomAD MT population frequency data for the variant.
Key
# | Section | Description |
---|---|---|
1 | Population | Data is provided by population within the study. Population is only visible where homoplasmic allele count > 0 |
2 | Homoplasmic allele frequency | Proportion of individuals carrying the homoplasmic variant allele within the population dataset |
3 | Homoplasmic allele count | Number of individuals within the population dataset carrying the mitochondrial variant in a homoplasmic state |
4 | Allele number - total number of alleles | Total count of reference alleles and variant alleles observed in the population dataset for that variant. N.B. this value is not available for the Genomics England dataset |
GEL internal¶
Genomics England internal population frequency data. Currently the number of alternate alleles and the total number of alleles are not available to display in the New IB. Further details can be found in the rare disease pipeline user guide.
Key
# | Section | Description |
---|---|---|
1 | Population | Data is provided by population within the study |
2 | Alt allele frequency for the variant | Frequency of the variant within the population dataset |
Segregation information¶
The segregation information card provides information on variant segregation for the proband and relatives.
The table can acommodate up to five individuals. The segregation is currently only available for variants that are included in the Interpreted Genome (Tiers 1,2,3), as this annotation is generated by and comes from the RD pipeline.
Key
# | Section | Description |
---|---|---|
1 | Zygosity | Relationship between the alleles at the locus |
2 | Proband / Mother / Father etc. | A column per related individual is displayed, up to a maximum of 5 |
3 | Affected status | The affected status of the individual (Affected, Unaffected, or Uncertain) |
4 | Patient ID | Genomics England patient identifier |
5 | Sample ID | Genomics England sample identifier |
6 | Zygosity | Visual representation of the zygosity for the individual. See the Zygosity visualisation section for further details |
7 | Alt reads | Number of variant-supporting reads for the individual |
8 | Ref reads | Number of reference-supporting reads for the individual |
9 | Total reads | Total number of reads for the individual (ref reads + alt reads) |
Zygosity visualisation¶
Zygosity is visualised according to the below criteria. For mitochondrial variants, Dragen 4 uses AF thresholds to determine the plasmy (Heteroplasmic = AF < 0.95, homoplasmic = AF ≥ 0.95).
N.B. As the sample is blood, for mitochondrial variants the plasmy may not be representative of that of the tissue related to the disease
- No call and unknown represent missing data where no genotype is available
- Half missing represents where one allele is observed but the other allele's data is missing
Other databases¶
The other databases information card displays a table with information about the variant classifications. Currently, only ClinVar classifications are displayed here.
N.B. these annotations are static and added at the time of analysis of the case by the pipeline
ClinVar¶
Key
# | Section | Description |
---|---|---|
1 | Accession | ClinVar Variation identifier for the variant (uniquely identifies the variant in ClinVar) |
2 | Review status | ClinVar Level of review supporting the variant classification |
3 | Submissions | Number of ClinVar submissions contributing to the review status |
4 | Classification | ClinVar aggregate classification for the variant |
5 | Interpretation | Total submissions for each classification category, across all ClinVar submissions for the variant (Pathogenic, Likely Pathogenic, Uncertain significance, Likely benign, Benign). IF the count for any category is 0 then that classification category is not displayed. |
6 | Last submission | Latest submission for the variant at the time of analysis by the pipeline |
Prioritisation results¶
The prioritisation results card displays details about the Genomics England Tiering outcome for the variant.
The highest Tier assigned to the variant and the clinical indication for the proband are displayed at the top of the card.
Below this we see all prioritisation results (previously known as Report Events) for the variant displayed in a table; the gene, panel, and the variant segregation, inheritance and penetrance considered by Tiering as part of the finding are displayed per prioritisation result.
Key
# | Section | Description |
---|---|---|
1 | Tooltip | Provides additional information about the section |
2 | Tiering | Button for the Genomics England Rare Disease Tiering tab |
3 | Highest Tier | The highest Tier assigned to the variant by Genomics England Rare Disease Tiering |
4 | Clinical indication | The clinical indication for the proband |
5 | Tier | Tier assigned by Genomics England Rare Disease Tiering |
6 | Gene | Gene for the Genomics England Rare Disease Tiering result |
7 | Gene colour | The gene is coloured green when it is green in the most recent PanelApp version, and that panel matches the GMS PanelApp panel applied to the patient (i.e. it is counterpart to the GMS version). |
8 | Variant segregation | The segregation that the variant fits with and that led to this Tiering outcome - it may be any of these terms |
9 | Variant MOI | The mode of inheritance that the variant fits with and that led to this Tiering outcome - it may be any of these terms. |
10 | Variant penetrance | Variant penetrance |
11 | GMS panel name | Name of the GMS panel applied to the patient that is associated with the Genomics England Rare Disease Tiering result, with a link to the GMS signed off PanelApp panel |
12 | Learn more about tiering | Link to the Genomics England Rare Disease Genome Analysis Guide |
Abbreviations
Abbreviation | Definition |
---|---|
ACGS | Association for Clinical Genomic Science |
ACMG | American College of Medical Genetics and Genomics |
CDS | Coding DNA Sequence |
CNV | Copy Number Variant |
CVA | Clinical Variant Ark |
New IB | New Interpretation Browser |
GEL | Genomics England |
GMS | Genomic Medicine Service |
GLH | Genomic Laboratory Hub |
HGVS | Human Genome Variation Society |
HTML | Hyper Text Markup Language |
HSCN | Health and Social Care Network (N3) |
IGV | Integrative Genomics Viewer |
IP | Interpretation Portal |
NGIS | National Genomics Informatics System |
PID | Patient Identifiable Data |
QC | Quality Control |
SO | Sequence Ontology |
SNV | Single Nucleotide Variant |
SV | Structural Variant |
TOMS | Test Order Management Service |
UAT | User Acceptance Testing |
VCF | Variant Call Format File |
WGS | Whole Genome Sequencing |