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dbSNP Short Genetic Variations

Welcome to the Reference SNP (rs) Report

All alleles are reported in the Forward orientation. Click on the Variant Details tab for details on Genomic Placement, Gene, and Amino Acid changes. HGVS names are in the HGVS tab.

Reference SNP (rs) Report

This page reports data for a single dbSNP Reference SNP variation (RefSNP or rs) from the new redesigned dbSNP build.
Top of the page reports a concise summary for the rs, with more specific details included in the corresponding tabs below.
All alleles are reported in the Forward orientation. Use the Genomic View to inspect the nucleotides flanking the variant, and its neighbors.
For more information see Help documentation.

rs1491330530

Current Build 156

Released September 21, 2022

Organism
Homo sapiens
Position
chr2:165927296 (GRCh38.p14) Help

The anchor position for this RefSNP. Includes all nucleotides potentially affected by this change, thus it can differ from HGVS, which is right-shifted. See here for details.

Alleles
insCA
Variation Type
Indel Insertion and Deletion
Frequency
insCA=0.00000 (0/11862, ALFA)
Clinical Significance
Not Reported in ClinVar
Gene : Consequence
TTC21B : Intron Variant
Publications
0 citations
Genomic View
See rs on genome

ALFA Allele Frequency
The ALFA project provide aggregate allele frequency from dbGaP. More information is available on the project page including descriptions, data access, and terms of use.

Release Version: 20231103111315
Population Group Sample Size Ref Allele Alt Allele Ref HMOZ Alt HMOZ HTRZ HWEP
Total Global 11862 A=1.00000 ACA=0.00000 1.0 0.0 0.0 N/A
European Sub 7618 A=1.0000 ACA=0.0000 1.0 0.0 0.0 N/A
African Sub 2816 A=1.0000 ACA=0.0000 1.0 0.0 0.0 N/A
African Others Sub 108 A=1.000 ACA=0.000 1.0 0.0 0.0 N/A
African American Sub 2708 A=1.0000 ACA=0.0000 1.0 0.0 0.0 N/A
Asian Sub 108 A=1.000 ACA=0.000 1.0 0.0 0.0 N/A
East Asian Sub 84 A=1.00 ACA=0.00 1.0 0.0 0.0 N/A
Other Asian Sub 24 A=1.00 ACA=0.00 1.0 0.0 0.0 N/A
Latin American 1 Sub 146 A=1.000 ACA=0.000 1.0 0.0 0.0 N/A
Latin American 2 Sub 610 A=1.000 ACA=0.000 1.0 0.0 0.0 N/A
South Asian Sub 94 A=1.00 ACA=0.00 1.0 0.0 0.0 N/A
Other Sub 470 A=1.000 ACA=0.000 1.0 0.0 0.0 N/A


Help

Frequency tab displays a table of the reference and alternate allele frequencies reported by various studies and populations. Table lines, where Population="Global" refer to the entire study population, whereas lines, where Group="Sub", refer to a study-specific population subgroupings (i.e. AFR, CAU, etc.), if available. Frequency for the alternate allele (Alt Allele) is a ratio of samples observed-to-total, where the numerator (observed samples) is the number of chromosomes in the study with the minor allele present (found in "Sample size", where Group="Sub"), and the denominator (total samples) is the total number of all chromosomes in the study for the variant (found in "Sample size", where Group="Study-wide" and Population="Global").

Download
Study Population Group Sample Size Ref Allele Alt Allele
Allele Frequency Aggregator Total Global 11862 A=1.00000 insCA=0.00000
Allele Frequency Aggregator European Sub 7618 A=1.0000 insCA=0.0000
Allele Frequency Aggregator African Sub 2816 A=1.0000 insCA=0.0000
Allele Frequency Aggregator Latin American 2 Sub 610 A=1.000 insCA=0.000
Allele Frequency Aggregator Other Sub 470 A=1.000 insCA=0.000
Allele Frequency Aggregator Latin American 1 Sub 146 A=1.000 insCA=0.000
Allele Frequency Aggregator Asian Sub 108 A=1.000 insCA=0.000
Allele Frequency Aggregator South Asian Sub 94 A=1.00 insCA=0.00
Help

Variant Details tab shows known variant placements on genomic sequences: chromosomes (NC_), RefSeqGene, pseudogenes or genomic regions (NG_), and in a separate table: on transcripts (NM_) and protein sequences (NP_). The corresponding transcript and protein locations are listed in adjacent lines, along with molecular consequences from Sequence Ontology. When no protein placement is available, only the transcript is listed. Column "Codon[Amino acid]" shows the actual base change in the format of "Reference > Alternate" allele, including the nucleotide codon change in transcripts, and the amino acid change in proteins, respectively, allowing for known ribosomal slippage sites. To view nucleotides adjacent to the variant use the Genomic View at the bottom of the page - zoom into the sequence until the nucleotides around the variant become visible.

Genomic Placements
Sequence name Change
GRCh38.p14 chr 2 NC_000002.12:g.165927296_165927297insCA
GRCh37.p13 chr 2 NC_000002.11:g.166783806_166783807insCA
TTC21B RefSeqGene NG_030345.1:g.31543_31544insGT
Gene: TTC21B, tetratricopeptide repeat domain 21B (minus strand)
Molecule type Change Amino acid[Codon] SO Term
TTC21B transcript NM_024753.5:c.1386+1839_1…

NM_024753.5:c.1386+1839_1386+1840insTG

N/A Intron Variant
TTC21B transcript variant X4 XM_006712761.2:c.1386+183…

XM_006712761.2:c.1386+1839_1386+1840insTG

N/A Intron Variant
TTC21B transcript variant X3 XM_011511871.4:c.636+1839…

XM_011511871.4:c.636+1839_636+1840insTG

N/A Intron Variant
TTC21B transcript variant X5 XM_011511872.3:c.1386+183…

XM_011511872.3:c.1386+1839_1386+1840insTG

N/A Intron Variant
TTC21B transcript variant X1 XM_017004967.2:c.1386+183…

XM_017004967.2:c.1386+1839_1386+1840insTG

N/A Intron Variant
TTC21B transcript variant X2 XM_047445870.1:c.732+1839…

XM_047445870.1:c.732+1839_732+1840insTG

N/A Intron Variant
Help

Clinical Significance tab shows a list of clinical significance entries from ClinVar associated with the variation, per allele. Click on the RCV accession (i.e. RCV000001615.2) or Allele ID (i.e. 12274) to access full ClinVar report.

Not Reported in ClinVar
Help

Aliases tab displays HGVS names representing the variant placements and allele changes on genomic, transcript and protein sequences, per allele. HGVS name is an expression for reporting sequence accession and version, sequence type, position, and allele change. The column "Note" can have two values: "diff" means that there is a difference between the reference allele (variation interval) at the placement reported in HGVS name and the reference alleles reported in other HGVS names, and "rev" means that the sequence of this variation interval at the placement reported in HGVS name is in reverse orientation to the sequence(s) of this variation in other HGVS names not labeled as "rev".

Placement A= insCA
GRCh38.p14 chr 2 NC_000002.12:g.165927296= NC_000002.12:g.165927296_165927297insCA
GRCh37.p13 chr 2 NC_000002.11:g.166783806= NC_000002.11:g.166783806_166783807insCA
TTC21B RefSeqGene NG_030345.1:g.31543= NG_030345.1:g.31543_31544insGT
TTC21B transcript NM_024753.4:c.1386+1839= NM_024753.4:c.1386+1839_1386+1840insTG
TTC21B transcript NM_024753.5:c.1386+1839= NM_024753.5:c.1386+1839_1386+1840insTG
TTC21B transcript variant X4 XM_006712761.2:c.1386+1839= XM_006712761.2:c.1386+1839_1386+1840insTG
TTC21B transcript variant X3 XM_011511871.4:c.636+1839= XM_011511871.4:c.636+1839_636+1840insTG
TTC21B transcript variant X5 XM_011511872.3:c.1386+1839= XM_011511872.3:c.1386+1839_1386+1840insTG
TTC21B transcript variant X1 XM_017004967.2:c.1386+1839= XM_017004967.2:c.1386+1839_1386+1840insTG
TTC21B transcript variant X2 XM_047445870.1:c.732+1839= XM_047445870.1:c.732+1839_732+1840insTG
Help

Submissions tab displays variations originally submitted to dbSNP, now supporting this RefSNP cluster (rs). We display Submitter handle, Submission identifier, Date and Build number, when the submission appeared for the first time. Direct submissions to dbSNP have Submission ID in the form of an ss-prefixed number (ss#). Other supporting variations are listed in the table without ss#.

1 Frequency submission
No Submitter Submission ID Date (Build)
1 ALFA NC_000002.12 - 165927296 Apr 26, 2021 (155)
Help

History tab displays RefSNPs (Associated ID) from previous builds (Build) that now support the current RefSNP, and the dates, when the history was updated for each Associated ID (History Updated).

Added to this RefSNP Cluster:
Submission IDs Observation SPDI Canonical SPDI Source RSIDs
11109385390 NC_000002.12:165927295:A:ACA NC_000002.12:165927295:A:ACA (self)
Removed from this RefSNP Cluster:
Submission IDs Observation SPDI Canonical SPDI Destination RSIDs
ss3329261889 NC_000002.12:165927295::AC NC_000002.12:165927295:A:ACA
Help

Publications tab displays PubMed articles citing the variation as a listing of PMID, Title, Author, Year, Journal, ordered by Year, descending.

No publications for rs1491330530

Help

The Flanks tab provides retrieving flanking sequences of a SNP on all molecules that have placements.

Genome context:
Select flank length:

Genomic regions, transcripts, and products
Top Help

NCBI Graphical Sequence Viewer display of the genomic region, transcripts and protein products for the reported RefSNP (rs).
Use the zoom option to view the nucleotides around the RefSNP and find other neighboring RefSNPs.
Visit Sequence Viewer for help with navigating inside the display and modifying the selection of displayed data tracks.

Software version is: 2.0.1.post820+afb47a3d