rs76001008

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000747.3(CHRNB1):​c.821-9C>T variant causes a splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0181 in 1,605,916 control chromosomes in the GnomAD database, including 321 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.014 ( 26 hom., cov: 30)
Exomes 𝑓: 0.019 ( 295 hom. )

Consequence

CHRNB1
NM_000747.3 splice_polypyrimidine_tract, intron

Scores

2
Splicing: ADA: 0.00002066
2

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: 0.925
Variant links:
Genes affected
CHRNB1 (HGNC:1961): (cholinergic receptor nicotinic beta 1 subunit) The muscle acetylcholine receptor is composed of five subunits: two alpha subunits and one beta, one gamma, and one delta subunit. This gene encodes the beta subunit of the acetylcholine receptor. The acetylcholine receptor changes conformation upon acetylcholine binding leading to the opening of an ion-conducting channel across the plasma membrane. Mutations in this gene are associated with slow-channel congenital myasthenic syndrome. [provided by RefSeq, Jul 2008]

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -20 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.7).
BP6
Variant 17-7454288-C-T is Benign according to our data. Variant chr17-7454288-C-T is described in ClinVar as [Benign]. Clinvar id is 128753.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-7454288-C-T is described in Lovd as [Benign].
BS1
Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.0137 (2088/152276) while in subpopulation NFE AF= 0.0211 (1436/68014). AF 95% confidence interval is 0.0202. There are 26 homozygotes in gnomad4. There are 963 alleles in male gnomad4 subpopulation. Median coverage is 30. This position pass quality control queck.
BS2
High Homozygotes in GnomAd4 at 26 AD,AR gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CHRNB1NM_000747.3 linkuse as main transcriptc.821-9C>T splice_polypyrimidine_tract_variant, intron_variant ENST00000306071.7 NP_000738.2

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CHRNB1ENST00000306071.7 linkuse as main transcriptc.821-9C>T splice_polypyrimidine_tract_variant, intron_variant 1 NM_000747.3 ENSP00000304290 P1P11230-1

Frequencies

GnomAD3 genomes
AF:
0.0137
AC:
2087
AN:
152158
Hom.:
26
Cov.:
30
show subpopulations
Gnomad AFR
AF:
0.00372
Gnomad AMI
AF:
0.0473
Gnomad AMR
AF:
0.00851
Gnomad ASJ
AF:
0.0452
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00642
Gnomad FIN
AF:
0.00904
Gnomad MID
AF:
0.0127
Gnomad NFE
AF:
0.0211
Gnomad OTH
AF:
0.0172
GnomAD3 exomes
AF:
0.0147
AC:
3684
AN:
251452
Hom.:
45
AF XY:
0.0150
AC XY:
2041
AN XY:
135902
show subpopulations
Gnomad AFR exome
AF:
0.00246
Gnomad AMR exome
AF:
0.00743
Gnomad ASJ exome
AF:
0.0399
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00542
Gnomad FIN exome
AF:
0.0111
Gnomad NFE exome
AF:
0.0216
Gnomad OTH exome
AF:
0.0199
GnomAD4 exome
AF:
0.0185
AC:
26935
AN:
1453640
Hom.:
295
Cov.:
31
AF XY:
0.0184
AC XY:
13324
AN XY:
723748
show subpopulations
Gnomad4 AFR exome
AF:
0.00270
Gnomad4 AMR exome
AF:
0.00805
Gnomad4 ASJ exome
AF:
0.0412
Gnomad4 EAS exome
AF:
0.0000756
Gnomad4 SAS exome
AF:
0.00495
Gnomad4 FIN exome
AF:
0.0119
Gnomad4 NFE exome
AF:
0.0210
Gnomad4 OTH exome
AF:
0.0173
GnomAD4 genome
AF:
0.0137
AC:
2088
AN:
152276
Hom.:
26
Cov.:
30
AF XY:
0.0129
AC XY:
963
AN XY:
74456
show subpopulations
Gnomad4 AFR
AF:
0.00371
Gnomad4 AMR
AF:
0.00850
Gnomad4 ASJ
AF:
0.0452
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00643
Gnomad4 FIN
AF:
0.00904
Gnomad4 NFE
AF:
0.0211
Gnomad4 OTH
AF:
0.0170
Alfa
AF:
0.0201
Hom.:
28
Bravo
AF:
0.0138
Asia WGS
AF:
0.00260
AC:
9
AN:
3478
EpiCase
AF:
0.0237
EpiControl
AF:
0.0220

ClinVar

Significance: Benign
Submissions summary: Benign:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:4
Benign, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact Sciences-- -
Likely benign, no assertion criteria providedclinical testingGenetic Services Laboratory, University of Chicago-Likely benign based on allele frequency in 1000 Genomes Project or ESP global frequency and its presence in a patient with a rare or unrelated disease phenotype. NOT Sanger confirmed. -
Benign, criteria provided, single submitterclinical testingGeneDxMay 27, 2016This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitterclinical testingAthena DiagnosticsMay 18, 2021- -
Congenital myasthenic syndrome 2A Benign:1
Benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 29, 2024- -
not provided Benign:1
Benign, criteria provided, single submitternot providedBreakthrough Genomics, Breakthrough Genomics-- -
Congenital myasthenic syndrome 4C Benign:1
Benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaJan 12, 2018This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.70
CADD
Benign
12
DANN
Benign
0.78

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000021
dbscSNV1_RF
Benign
0.014
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs76001008; hg19: chr17-7357607; API