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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.

rs1491478953

Current Build 156

Released September 21, 2022

Organism
Homo sapiens
Position
chr2:174750180-174750181 (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
delCA
Variation Type
Deletion
Frequency
delCA=0.00039 (10/25936, GnomAD)
delCA=0.00000 (0/11862, ALFA)
Clinical Significance
Reported in ClinVar
Gene : Consequence
CHRNA1 : 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 CA=1.00000 =0.00000 1.0 0.0 0.0 N/A
European Sub 7618 CA=1.0000 =0.0000 1.0 0.0 0.0 N/A
African Sub 2816 CA=1.0000 =0.0000 1.0 0.0 0.0 N/A
African Others Sub 108 CA=1.000 =0.000 1.0 0.0 0.0 N/A
African American Sub 2708 CA=1.0000 =0.0000 1.0 0.0 0.0 N/A
Asian Sub 108 CA=1.000 =0.000 1.0 0.0 0.0 N/A
East Asian Sub 84 CA=1.00 =0.00 1.0 0.0 0.0 N/A
Other Asian Sub 24 CA=1.00 =0.00 1.0 0.0 0.0 N/A
Latin American 1 Sub 146 CA=1.000 =0.000 1.0 0.0 0.0 N/A
Latin American 2 Sub 610 CA=1.000 =0.000 1.0 0.0 0.0 N/A
South Asian Sub 94 CA=1.00 =0.00 1.0 0.0 0.0 N/A
Other Sub 470 CA=1.000 =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
gnomAD - Genomes Global Study-wide 25936 CA=0.99961 delCA=0.00039
gnomAD - Genomes European Sub 12022 CA=0.99950 delCA=0.00050
gnomAD - Genomes African Sub 11226 CA=0.99982 delCA=0.00018
gnomAD - Genomes American Sub 1496 CA=0.9993 delCA=0.0007
gnomAD - Genomes Ashkenazi Jewish Sub 688 CA=1.000 delCA=0.000
gnomAD - Genomes Other Sub 366 CA=0.997 delCA=0.003
gnomAD - Genomes East Asian Sub 138 CA=1.000 delCA=0.000
Allele Frequency Aggregator Total Global 11862 CA=1.00000 delCA=0.00000
Allele Frequency Aggregator European Sub 7618 CA=1.0000 delCA=0.0000
Allele Frequency Aggregator African Sub 2816 CA=1.0000 delCA=0.0000
Allele Frequency Aggregator Latin American 2 Sub 610 CA=1.000 delCA=0.000
Allele Frequency Aggregator Other Sub 470 CA=1.000 delCA=0.000
Allele Frequency Aggregator Latin American 1 Sub 146 CA=1.000 delCA=0.000
Allele Frequency Aggregator Asian Sub 108 CA=1.000 delCA=0.000
Allele Frequency Aggregator South Asian Sub 94 CA=1.00 delCA=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.174750180_174750181del
GRCh37.p13 chr 2 NC_000002.11:g.175614908_175614909del
CHRNA1 RefSeqGene NG_008172.1:g.19292_19293del
Gene: CHRNA1, cholinergic receptor nicotinic alpha 1 subunit (minus strand)
Molecule type Change Amino acid[Codon] SO Term
CHRNA1 transcript variant 2 NM_000079.4:c.779-12_779-…

NM_000079.4:c.779-12_779-11del

N/A Intron Variant
CHRNA1 transcript variant 1 NM_001039523.3:c.854-12_8…

NM_001039523.3:c.854-12_854-11del

N/A Intron Variant
CHRNA1 transcript variant X1 XM_017003256.2:c.875-12_8…

XM_017003256.2:c.875-12_875-11del

N/A Intron Variant
CHRNA1 transcript variant X2 XM_017003257.2:c.800-12_8…

XM_017003257.2:c.800-12_800-11del

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.

Allele: delCA (allele ID: 282964 )
ClinVar Accession Disease Names Clinical Significance
RCV000283001.3 Autosomal recessive multiple pterygium syndrome Uncertain-Significance
RCV000342138.3 Congenital Myasthenic Syndrome, Dominant/Recessive Uncertain-Significance
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 CA= delCA
GRCh38.p14 chr 2 NC_000002.12:g.174750180_174750181= NC_000002.12:g.174750180_174750181del
GRCh37.p13 chr 2 NC_000002.11:g.175614908_175614909= NC_000002.11:g.175614908_175614909del
CHRNA1 RefSeqGene NG_008172.1:g.19292_19293= NG_008172.1:g.19292_19293del
CHRNA1 transcript variant 2 NM_000079.3:c.779-11= NM_000079.3:c.779-12_779-11del
CHRNA1 transcript variant 2 NM_000079.4:c.779-11= NM_000079.4:c.779-12_779-11del
CHRNA1 transcript variant 1 NM_001039523.2:c.854-11= NM_001039523.2:c.854-12_854-11del
CHRNA1 transcript variant 1 NM_001039523.3:c.854-11= NM_001039523.3:c.854-12_854-11del
CHRNA1 transcript variant X1 XM_017003256.2:c.875-11= XM_017003256.2:c.875-12_875-11del
CHRNA1 transcript variant X2 XM_017003257.2:c.800-11= XM_017003257.2:c.800-12_800-11del
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#.

8 SubSNP, 2 Frequency, 2 ClinVar submissions
No Submitter Submission ID Date (Build)
1 CLINVAR ss2137088785 Oct 11, 2018 (152)
2 GNOMAD ss2746820083 Jan 10, 2018 (151)
3 GNOMAD ss2783073241 Jan 10, 2018 (151)
4 EVA_DECODE ss3705471814 Jul 13, 2019 (153)
5 EVA ss3986204861 Apr 26, 2021 (155)
6 EVA ss5848528399 Oct 12, 2022 (156)
7 EVA ss5848528401 Oct 12, 2022 (156)
8 EVA ss5848528402 Oct 12, 2022 (156)
9 gnomAD - Genomes NC_000002.12 - 174750180 Apr 26, 2021 (155)
10 ALFA NC_000002.12 - 174750180 Apr 26, 2021 (155)
11 ClinVar RCV000283001.3 Oct 12, 2022 (156)
12 ClinVar RCV000342138.3 Oct 12, 2022 (156)
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
ss2746820083, ss2783073241, ss3986204861, ss5848528399, ss5848528401, ss5848528402 NC_000002.11:175614907:CA: NC_000002.12:174750179:CA: (self)
RCV000283001.3, RCV000342138.3, 82527068, 12667245535, ss2137088785, ss3705471814 NC_000002.12:174750179:CA: NC_000002.12:174750179:CA: (self)
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 rs1491478953

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