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dbSNP Short Genetic Variations

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 151

Released July 17, 2018

Homo sapiens
chr21:31667299 (GRCh38.p7) 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>C
Variation Type
SNV Single Nucleotide Variation
A=0.00001 (3/246262, GnomAD)
Clinical Significance
Reported in ClinVar
Gene : Consequence
SOD1 : Missense Variant
4 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.p7 chr 21 NC_000021.9:g.31667299G>A
GRCh38.p7 chr 21 NC_000021.9:g.31667299G>C
GRCh37.p13 chr 21 NC_000021.8:g.33039612G>A
GRCh37.p13 chr 21 NC_000021.8:g.33039612G>C
SOD1 RefSeqGene (LRG_652) NG_008689.1:g.12678G>A
SOD1 RefSeqGene (LRG_652) NG_008689.1:g.12678G>C
Gene: SOD1, superoxide dismutase 1, soluble (plus strand)
Molecule type Change Amino acid[Codon] SO Term
SOD1 transcript NM_000454.4:c.281G>A G [GGT] > D [GAT] Coding Sequence Variant
superoxide dismutase [Cu-Zn] NP_000445.1:p.Gly...


G (Gly) > D (Asp) Missense Variant
SOD1 transcript NM_000454.4:c.281G>C G [GGT] > A [GCT] Coding Sequence Variant
superoxide dismutase [Cu-Zn] NP_000445.1:p.Gly...


G (Gly) > A (Ala) Missense Variant

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.

Allele: C (allele ID: 29799 )
ClinVar Accession Disease Names Clinical Significance
RCV000015882.26 Amyotrophic lateral sclerosis type 1 Pathogenic

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
The Genome Aggregation Database Global Study-wide 246262 G=0.99998 A=0.00001, C=0.00001
The Genome Aggregation Database European Sub 134010 G=0.99996 A=0.00002, C=0.00001
The Genome Aggregation Database Asian Sub 48030 G=1.0000 A=0.0000, C=0.0000
The Genome Aggregation Database American Sub 33582 G=1.0000 A=0.0000, C=0.0000
The Genome Aggregation Database African Sub 15304 G=1.0000 A=0.0000, C=0.0000
The Genome Aggregation Database Ashkenazi Jewish Sub 9850 G=1.000 A=0.000, C=0.000
The Genome Aggregation Database Other Sub 5486 G=1.000 A=0.000, C=0.000

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 C Note
GRCh38.p7 chr 21 NC_000021.9:g.316...






GRCh37.p13 chr 21 NC_000021.8:g.330...






SOD1 RefSeqGene (LRG_652) NG_008689.1:g.126...






SOD1 transcript NM_000454.4:c.281G= NM_000454.4:c.281G>A NM_000454.4:c.281G>C
superoxide dismutase [Cu-Zn] NP_000445.1:p.Gly94= NP_000445.1:p.Gly...





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 ClinVar, 1 Frequency, 5 SubSNP submissions
No Submitter Submission ID Date (Build)
1 OMIM-CURATED-RECORDS ss275486801 Nov 19, 2010 (133)
2 ILLUMINA ss1959948534 Feb 12, 2016 (147)
3 GNOMAD ss2744804169 Nov 08, 2017 (151)
4 ILLUMINA ss3022154430 Nov 08, 2017 (151)
5 ILLUMINA ss3625795647 Jul 20, 2018 (151)
6 The Genome Aggregation Database NC_000021.8 - 33039612 Jul 20, 2018 (151)
7 ClinVar RCV000015882.26 Jul 20, 2018 (151)

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
13818904, ss1959948534, ss2744804169, ss3022154430, ss3625795647 NC_000021.8:33039611:G= NC_000021.9:31667298:G= (self)
ss275486801 NC_000021.9:31667298:G= NC_000021.9:31667298:G= (self)
13818904, ss2744804169 NC_000021.8:33039611:G>A NC_000021.9:31667298:G>A (self)
13818904, ss1959948534, ss2744804169, ss3022154430, ss3625795647 NC_000021.8:33039611:G>C NC_000021.9:31667298:G>C (self)
RCV000015882.26, ss275486801 NC_000021.9:31667298:G>C NC_000021.9:31667298:G>C (self)

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

4 citations for rs121912438
PMID Title Author Year Journal
8446170 Mutations in Cu/Zn superoxide dismutase gene are associated with familial amyotrophic lateral sclerosis. Rosen DR et al. 1993 Nature
8560268 Altered reactivity of superoxide dismutase in familial amyotrophic lateral sclerosis. Wiedau-Pazos M et al. 1996 Science (New York, N.Y.)
8650157 A gain-of-function of an amyotrophic lateral sclerosis-associated Cu,Zn-superoxide dismutase mutant: An enhancement of free radical formation due to a decrease in Km for hydrogen peroxide. Yim MB et al. 1996 Proceedings of the National Academy of Sciences of the United States of America
9228005 Bcl-2: prolonging life in a transgenic mouse model of familial amyotrophic lateral sclerosis. Kostic V et al. 1997 Science (New York, N.Y.)

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: 0.1.4.post833+d3ba21e