17-7448570-C-T

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_000747.3(CHRNB1):​c.611-9C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000438 in 1,613,908 control chromosomes in the GnomAD database, including 8 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). There are indicators that this mutation may affect the branch point..

Frequency

Genomes: 𝑓 0.00022 ( 0 hom., cov: 31)
Exomes 𝑓: 0.00046 ( 8 hom. )

Consequence

CHRNB1
NM_000747.3 intron

Scores

2
Splicing: ADA: 0.00002517
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:2

Conservation

PhyloP100: -0.253

Publications

0 publications found
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]
CHRNB1 Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 2C
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • congenital myasthenic syndrome 1A
    Inheritance: AD Classification: STRONG Submitted by: PanelApp Australia
  • congenital myasthenic syndrome 2A
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
  • postsynaptic congenital myasthenic syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -20 ACMG points.

BP4
This position, referring to a specific DNA site, is a probable branch point but is likely benign (scored 2 / 10, using the threshold of <=3). The score ranges from 0 to 10, with values ≤3 considered benign and >5 classified as pathogenic. Computational evidence support a benign effect (BayesDel_noAF=-0.87).
BP6
Variant 17-7448570-C-T is Benign according to our data. Variant chr17-7448570-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 476152.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population sas. GnomAd4 allele frequency = 0.000217 (33/152310) while in subpopulation SAS AF = 0.00683 (33/4832). AF 95% confidence interval is 0.005. There are 0 homozygotes in GnomAd4. There are 29 alleles in the male GnomAd4 subpopulation. Median coverage is 31. This position passed quality control check.
BS2
High Homozygotes in GnomAdExome4 at 8 AR,AD gene

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000747.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNB1
NM_000747.3
MANE Select
c.611-9C>T
intron
N/ANP_000738.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNB1
ENST00000306071.7
TSL:1 MANE Select
c.611-9C>T
intron
N/AENSP00000304290.2
CHRNB1
ENST00000536404.6
TSL:2
c.395-9C>T
intron
N/AENSP00000439209.2
CHRNB1
ENST00000576360.1
TSL:3
c.395-9C>T
intron
N/AENSP00000459092.1

Frequencies

GnomAD3 genomes
AF:
0.000217
AC:
33
AN:
152192
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00682
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000890
AC:
223
AN:
250606
AF XY:
0.00122
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000327
GnomAD4 exome
AF:
0.000461
AC:
674
AN:
1461598
Hom.:
8
Cov.:
32
AF XY:
0.000678
AC XY:
493
AN XY:
727092
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.0000224
AC:
1
AN:
44710
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00739
AC:
637
AN:
86218
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5762
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111800
Other (OTH)
AF:
0.000530
AC:
32
AN:
60386
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.471
Heterozygous variant carriers
0
44
88
133
177
221
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000217
AC:
33
AN:
152310
Hom.:
0
Cov.:
31
AF XY:
0.000389
AC XY:
29
AN XY:
74484
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41562
American (AMR)
AF:
0.00
AC:
0
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00683
AC:
33
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.514
Heterozygous variant carriers
0
3
5
8
10
13
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000427
Hom.:
0
Bravo
AF:
0.0000642
Asia WGS
AF:
0.00231
AC:
8
AN:
3478

ClinVar

ClinVar submissions as Germline

Significance:Benign/Likely benign
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
1
Congenital myasthenic syndrome 2A (1)
-
-
1
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.87
CADD
Benign
7.2
DANN
Benign
0.36
PhyloP100
-0.25
BranchPoint Hunter
2.0
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.000025
dbscSNV1_RF
Benign
0.0020
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs538827412; hg19: chr17-7351889; API