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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.

rs1491578043

Current Build 156

Released September 21, 2022

Organism
Homo sapiens
Position
chr21:18145432-18145434 (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
delTT / delT
Variation Type
Indel Insertion and Deletion
Frequency
delTT=0.00010 (9/90432, GnomAD)
delTT=0.00017 (2/11826, ALFA)
Clinical Significance
Not Reported in ClinVar
Gene : Consequence
CHODL : 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 11826 TTT=0.99983 T=0.00017 0.999662 0.0 0.000338 0
European Sub 7618 TTT=1.0000 T=0.0000 1.0 0.0 0.0 N/A
African Sub 2782 TTT=0.9993 T=0.0007 0.998562 0.0 0.001438 0
African Others Sub 106 TTT=1.000 T=0.000 1.0 0.0 0.0 N/A
African American Sub 2676 TTT=0.9993 T=0.0007 0.998505 0.0 0.001495 0
Asian Sub 108 TTT=1.000 T=0.000 1.0 0.0 0.0 N/A
East Asian Sub 84 TTT=1.00 T=0.00 1.0 0.0 0.0 N/A
Other Asian Sub 24 TTT=1.00 T=0.00 1.0 0.0 0.0 N/A
Latin American 1 Sub 146 TTT=1.000 T=0.000 1.0 0.0 0.0 N/A
Latin American 2 Sub 610 TTT=1.000 T=0.000 1.0 0.0 0.0 N/A
South Asian Sub 94 TTT=1.00 T=0.00 1.0 0.0 0.0 N/A
Other Sub 468 TTT=1.000 T=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 90432 TTT=0.99990 delTT=0.00010
gnomAD - Genomes European Sub 56930 TTT=0.99996 delTT=0.00004
gnomAD - Genomes African Sub 18290 TTT=0.99962 delTT=0.00038
gnomAD - Genomes American Sub 8500 TTT=1.0000 delTT=0.0000
gnomAD - Genomes Ashkenazi Jewish Sub 2760 TTT=1.0000 delTT=0.0000
gnomAD - Genomes East Asian Sub 2706 TTT=1.0000 delTT=0.0000
gnomAD - Genomes Other Sub 1246 TTT=1.0000 delTT=0.0000
Allele Frequency Aggregator Total Global 11826 TTT=0.99983 delTT=0.00017
Allele Frequency Aggregator European Sub 7618 TTT=1.0000 delTT=0.0000
Allele Frequency Aggregator African Sub 2782 TTT=0.9993 delTT=0.0007
Allele Frequency Aggregator Latin American 2 Sub 610 TTT=1.000 delTT=0.000
Allele Frequency Aggregator Other Sub 468 TTT=1.000 delTT=0.000
Allele Frequency Aggregator Latin American 1 Sub 146 TTT=1.000 delTT=0.000
Allele Frequency Aggregator Asian Sub 108 TTT=1.000 delTT=0.000
Allele Frequency Aggregator South Asian Sub 94 TTT=1.00 delTT=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 21 NC_000021.9:g.18145433_18145434del
GRCh38.p14 chr 21 NC_000021.9:g.18145434del
GRCh37.p13 chr 21 NC_000021.8:g.19517750_19517751del
GRCh37.p13 chr 21 NC_000021.8:g.19517751del
CHODL RefSeqGene NG_029478.1:g.233094_233095del
CHODL RefSeqGene NG_029478.1:g.233095del
Gene: CHODL, chondrolectin (plus strand)
Molecule type Change Amino acid[Codon] SO Term
CHODL transcript variant 3 NM_001204175.2:c.-44-1110…

NM_001204175.2:c.-44-111076_-44-111075del

N/A Intron Variant
CHODL transcript variant 4 NM_001204176.2:c.-44-1110…

NM_001204176.2:c.-44-111076_-44-111075del

N/A Intron Variant
CHODL transcript variant 5 NM_001204177.2:c.-44-1110…

NM_001204177.2:c.-44-111076_-44-111075del

N/A Intron Variant
CHODL transcript variant 6 NM_001204178.2:c.-44-1110…

NM_001204178.2:c.-44-111076_-44-111075del

N/A Intron Variant
CHODL transcript variant 2 NM_001204174.2:c. N/A Genic Upstream Transcript Variant
CHODL transcript variant 1 NM_024944.3:c. N/A Genic Upstream Transcript Variant
CHODL transcript variant X2 XM_011529453.3:c. N/A Genic Upstream Transcript Variant
CHODL transcript variant X1 XM_017028273.2:c. N/A Genic Upstream Transcript Variant
CHODL transcript variant X3 XM_047440682.1:c. N/A Genic Upstream Transcript 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 TTT= delTT delT
GRCh38.p14 chr 21 NC_000021.9:g.18145432_18145434= NC_000021.9:g.18145433_18145434del NC_000021.9:g.18145434del
GRCh37.p13 chr 21 NC_000021.8:g.19517749_19517751= NC_000021.8:g.19517750_19517751del NC_000021.8:g.19517751del
CHODL RefSeqGene NG_029478.1:g.233093_233095= NG_029478.1:g.233094_233095del NG_029478.1:g.233095del
CHODL transcript variant 3 NM_001204175.2:c.-44-111077= NM_001204175.2:c.-44-111076_-44-111075del NM_001204175.2:c.-44-111075del
CHODL transcript variant 4 NM_001204176.1:c.-44-111077= NM_001204176.1:c.-44-111076_-44-111075del NM_001204176.1:c.-44-111075del
CHODL transcript variant 4 NM_001204176.2:c.-44-111077= NM_001204176.2:c.-44-111076_-44-111075del NM_001204176.2:c.-44-111075del
CHODL transcript variant 5 NM_001204177.2:c.-44-111077= NM_001204177.2:c.-44-111076_-44-111075del NM_001204177.2:c.-44-111075del
CHODL transcript variant 6 NM_001204178.1:c.-44-111077= NM_001204178.1:c.-44-111076_-44-111075del NM_001204178.1:c.-44-111075del
CHODL transcript variant 6 NM_001204178.2:c.-44-111077= NM_001204178.2:c.-44-111076_-44-111075del NM_001204178.2:c.-44-111075del
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#.

3 SubSNP, 2 Frequency submissions
No Submitter Submission ID Date (Build)
1 EVA_DECODE ss3707436888 Jul 13, 2019 (153)
2 EVA_DECODE ss3707436889 Jul 13, 2019 (153)
3 GNOMAD ss4357854521 Apr 27, 2021 (155)
4 gnomAD - Genomes NC_000021.9 - 18145432 Apr 27, 2021 (155)
5 ALFA NC_000021.9 - 18145432 Apr 27, 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
559061391, ss3707436888, ss4357854521 NC_000021.9:18145431:TT: NC_000021.9:18145431:TTT:T (self)
5695830837 NC_000021.9:18145431:TTT:T NC_000021.9:18145431:TTT:T (self)
ss3707436889 NC_000021.9:18145432:T: NC_000021.9:18145431:TTT:TT (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 rs1491578043

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