rs189442556

Variant summary

Our verdict is Benign. The variant received -18 ACMG points: 0P and 18B. BP4_ModerateBP6_Very_StrongBS1BS2

The NM_000079.4(CHRNA1):​c.723C>T​(p.Pro241Pro) variant causes a synonymous change. The variant allele was found at a frequency of 0.000593 in 1,614,200 control chromosomes in the GnomAD database, including 9 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00041 ( 1 hom., cov: 31)
Exomes 𝑓: 0.00061 ( 8 hom. )

Consequence

CHRNA1
NM_000079.4 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 3.60

Publications

1 publications found
Variant links:
Genes affected
CHRNA1 (HGNC:1955): (cholinergic receptor nicotinic alpha 1 subunit) The muscle acetylcholine receptor consiststs of 5 subunits of 4 different types: 2 alpha subunits and 1 each of the beta, gamma, and delta subunits. This gene encodes an alpha subunit that plays a role in acetlycholine binding/channel gating. Alternatively spliced transcript variants encoding different isoforms have been identified. [provided by RefSeq, Nov 2012]
CHRNA1 Gene-Disease associations (from GenCC):
  • congenital myasthenic syndrome 1A
    Inheritance: AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), PanelApp Australia
  • lethal multiple pterygium syndrome
    Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, G2P
  • myasthenic syndrome, congenital, 1B, fast-channel
    Inheritance: AR, AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, PanelApp Australia
  • 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 -18 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.46).
BP6
Variant 2-174753558-G-A is Benign according to our data. Variant chr2-174753558-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 493302.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 = 0.000407 (62/152306) while in subpopulation SAS AF = 0.0102 (49/4826). AF 95% confidence interval is 0.00789. There are 1 homozygotes in GnomAd4. There are 48 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_000079.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNA1
NM_000079.4
MANE Select
c.723C>Tp.Pro241Pro
synonymous
Exon 6 of 9NP_000070.1
CHRNA1
NM_001039523.3
c.798C>Tp.Pro266Pro
synonymous
Exon 7 of 10NP_001034612.1

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
CHRNA1
ENST00000348749.9
TSL:1 MANE Select
c.723C>Tp.Pro241Pro
synonymous
Exon 6 of 9ENSP00000261008.5
CHRNA1
ENST00000409323.1
TSL:1
c.723C>Tp.Pro241Pro
synonymous
Exon 6 of 6ENSP00000386684.1
ENSG00000236449
ENST00000442996.1
TSL:1
n.322-19191G>A
intron
N/A

Frequencies

GnomAD3 genomes
AF:
0.000407
AC:
62
AN:
152188
Hom.:
1
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.0101
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000162
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00115
AC:
288
AN:
251358
AF XY:
0.00160
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000123
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.000612
AC:
895
AN:
1461894
Hom.:
8
Cov.:
31
AF XY:
0.000903
AC XY:
657
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00881
AC:
760
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00225
AC:
13
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000728
AC:
81
AN:
1112012
Other (OTH)
AF:
0.000629
AC:
38
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.481
Heterozygous variant carriers
0
78
155
233
310
388
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
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:
0.000407
AC:
62
AN:
152306
Hom.:
1
Cov.:
31
AF XY:
0.000645
AC XY:
48
AN XY:
74476
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41560
American (AMR)
AF:
0.0000654
AC:
1
AN:
15296
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5190
South Asian (SAS)
AF:
0.0102
AC:
49
AN:
4826
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:
0.000162
AC:
11
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.509
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
Genome Hom
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:
0.000245
Hom.:
0
Bravo
AF:
0.0000831
Asia WGS
AF:
0.00231
AC:
8
AN:
3478
EpiCase
AF:
0.000436
EpiControl
AF:
0.000178

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Lethal multiple pterygium syndrome Benign:2
Nov 04, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease.

not provided Benign:2
Oct 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CHRNA1: PM2:Supporting, BP4, BP7

Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

Congenital myasthenic syndrome Benign:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This 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 likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease.

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.46
CADD
Benign
10
DANN
Benign
0.86
PhyloP100
3.6
Mutation Taster
=72/28
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
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: rs189442556; hg19: chr2-175618286; API