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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.


Current Build 155

Released April 9, 2021

Homo sapiens
chr21:13016422 (GRCh38.p13) 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.

G>A / G>T
Variation Type
SNV Single Nucleotide Variation
G=0.47261 (7921/16760, 8.3KJPN)
G=0.4876 (2756/5652, ALFA)
G=0.4727 (1385/2930, KOREAN) (+ 2 more)
G=0.470 (262/558, SGDP_PRJ)
G=0.468 (101/216, Qatari)
Clinical Significance
Not Reported in ClinVar
Gene : Consequence
0 citations
Genomic View
See rs on genome

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.p13 chr 21 NC_000021.9:g.13016422G>A
GRCh38.p13 chr 21 NC_000021.9:g.13016422G>T
GRCh37.p13 chr 21 NC_000021.8:g.14388743G>A
GRCh37.p13 chr 21 NC_000021.8:g.14388743G>T

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

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: 20201027095038
Population Group Sample Size Ref Allele Alt Allele
Total Global 5652 G=0.4876 A=0.5124, T=0.0000
European Sub 5118 G=0.4973 A=0.5027, T=0.0000
African Sub 522 G=0.393 A=0.607, T=0.000
African Others Sub 24 G=0.46 A=0.54, T=0.00
African American Sub 498 G=0.390 A=0.610, T=0.000
Asian Sub 0 G=0 A=0, T=0
East Asian Sub 0 G=0 A=0, T=0
Other Asian Sub 0 G=0 A=0, T=0
Latin American 1 Sub 0 G=0 A=0, T=0
Latin American 2 Sub 0 G=0 A=0, T=0
South Asian Sub 0 G=0 A=0, T=0
Other Sub 12 G=0.50 A=0.50, T=0.00


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").

Study Population Group Sample Size Ref Allele Alt Allele
8.3KJPN JAPANESE Study-wide 16760 G=0.47261 A=0.52739
KOREAN population from KRGDB KOREAN Study-wide 2930 G=0.4727 A=0.5273
SGDP_PRJ Global Study-wide 558 G=0.470 A=0.530
Qatari Global Study-wide 216 G=0.468 A=0.532

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 G= A T
GRCh38.p13 chr 21 NC_000021.9:g.13016422= NC_000021.9:g.13016422G>A NC_000021.9:g.13016422G>T
GRCh37.p13 chr 21 NC_000021.8:g.14388743= NC_000021.8:g.14388743G>A NC_000021.8:g.14388743G>T

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#.

28 SubSNP, 5 Frequency submissions
No Submitter Submission ID Date (Build)
1 SC_JCM ss684156 Aug 11, 2000 (83)
2 PERLEGEN ss3995632 Sep 28, 2001 (100)
3 TSC-CSHL ss5409607 Oct 08, 2002 (110)
4 TSC-CSHL ss5443163 Oct 08, 2002 (110)
5 WI_SSAHASNP ss12509450 Jul 11, 2003 (117)
6 WUGSC_SSAHASNP ss14444965 Dec 05, 2003 (119)
7 SC_SNP ss14743207 Dec 05, 2003 (119)
8 HGSV ss78970642 Dec 05, 2007 (129)
9 BCMHGSC_JDW ss91766789 Mar 24, 2008 (129)
10 HUMANGENOME_JCVI ss95824928 Feb 06, 2009 (130)
11 ILLUMINA-UK ss117448606 Dec 01, 2009 (131)
12 ENSEMBL ss135656772 Dec 01, 2009 (147)
13 GMI ss283460350 May 04, 2012 (137)
14 PJP ss292673861 May 09, 2011 (134)
15 DDI ss1429120786 Apr 01, 2015 (144)
16 WEILL_CORNELL_DGM ss1938466502 Feb 12, 2016 (147)
17 GRF ss2704318365 Nov 08, 2017 (151)
18 SWEGEN ss3018580007 Nov 08, 2017 (151)
19 CSHL ss3352626028 Nov 08, 2017 (151)
20 TOPMED ss3366035265 Nov 08, 2017 (151)
21 URBANLAB ss3651071823 Oct 12, 2018 (152)
22 PACBIO ss3788708548 Jul 13, 2019 (153)
23 PACBIO ss3793589851 Jul 13, 2019 (153)
24 PACBIO ss3798476086 Jul 13, 2019 (153)
25 KHV_HUMAN_GENOMES ss3822037805 Jul 13, 2019 (153)
26 SGDP_PRJ ss3889593639 Apr 27, 2020 (154)
27 KRGDB ss3939993485 Apr 27, 2020 (154)
28 TOMMO_GENOMICS ss5230695783 Apr 26, 2021 (155)
29 KOREAN population from KRGDB NC_000021.8 - 14388743 Apr 27, 2020 (154)
30 Qatari NC_000021.8 - 14388743 Apr 27, 2020 (154)
31 SGDP_PRJ NC_000021.8 - 14388743 Apr 27, 2020 (154)
32 8.3KJPN NC_000021.8 - 14388743 Apr 26, 2021 (155)
33 ALFA NC_000021.9 - 13016422 Apr 26, 2021 (155)

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).

Associated ID History Updated (Build)
rs3875612 Dec 16, 2002 (110)
rs8130849 Aug 27, 2003 (117)
rs77783280 Jul 19, 2016 (147)
Added to this RefSNP Cluster:
Submission IDs Observation SPDI Canonical SPDI Source RSIDs
ss78970642, ss91766789, ss117448606, ss283460350, ss292673861 NC_000021.7:13310613:G:A NC_000021.9:13016421:G:A (self)
47170879, 20508424, 41610619, 88665090, ss1429120786, ss1938466502, ss2704318365, ss3018580007, ss3352626028, ss3788708548, ss3793589851, ss3798476086, ss3889593639, ss3939993485, ss5230695783 NC_000021.8:14388742:G:A NC_000021.9:13016421:G:A (self)
2435809967, ss3366035265, ss3651071823, ss3822037805 NC_000021.9:13016421:G:A NC_000021.9:13016421:G:A (self)
ss12509450 NT_011512.8:50613:G:A NC_000021.9:13016421:G:A (self)
ss14444965, ss14743207 NT_011512.9:50613:G:A NC_000021.9:13016421:G:A (self)
ss684156, ss3995632, ss5409607, ss5443163, ss95824928, ss135656772 NT_011512.11:50613:G:A NC_000021.9:13016421:G:A (self)
2435809967 NC_000021.9:13016421:G:T NC_000021.9:13016421:G:T

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

No publications for rs513946


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.post596+ae089ad