2-174764382-G-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_000079.4(CHRNA1):​c.13C>A​(p.Pro5Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,613,258 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P5S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

CHRNA1
NM_000079.4 missense

Scores

19

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.169

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: Likely_benign. The variant received -1 ACMG points.

PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 16 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Gene score misZ: 0.72157 (below the threshold of 3.09). Trascript score misZ: 1.6771 (below the threshold of 3.09). GenCC associations: The gene is linked to lethal multiple pterygium syndrome, congenital myasthenic syndrome 1A, myasthenic syndrome, congenital, 1B, fast-channel, postsynaptic congenital myasthenic syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.07089156).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNA1NM_000079.4 linkc.13C>A p.Pro5Thr missense_variant Exon 1 of 9 ENST00000348749.9 NP_000070.1 P02708-2Q53SH4
CHRNA1NM_001039523.3 linkc.13C>A p.Pro5Thr missense_variant Exon 1 of 10 NP_001034612.1 P02708-1Q53SH4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNA1ENST00000348749.9 linkc.13C>A p.Pro5Thr missense_variant Exon 1 of 9 1 NM_000079.4 ENSP00000261008.5 P02708-2

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152196
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000402
AC:
1
AN:
248734
AF XY:
0.00000743
show subpopulations
Gnomad AFR exome
AF:
0.0000625
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461062
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
726732
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33476
American (AMR)
AF:
0.00
AC:
0
AN:
44650
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26110
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85982
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53344
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111696
Other (OTH)
AF:
0.00
AC:
0
AN:
60346
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152196
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.0000965
AC:
4
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15286
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000386
Hom.:
0
Bravo
AF:
0.0000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Aug 15, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.13C>A (p.P5T) alteration is located in exon 1 (coding exon 1) of the CHRNA1 gene. This alteration results from a C to A substitution at nucleotide position 13, causing the proline (P) at amino acid position 5 to be replaced by a threonine (T). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.082
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.37
CADD
Benign
11
DANN
Benign
0.96
DEOGEN2
Benign
0.15
.;T;T;T;.
Eigen
Benign
-0.99
Eigen_PC
Benign
-1.0
FATHMM_MKL
Benign
0.053
N
LIST_S2
Benign
0.70
T;T;T;T;T
M_CAP
Benign
0.026
D
MetaRNN
Benign
0.071
T;T;T;T;T
MetaSVM
Benign
-0.93
T
MutationAssessor
Benign
-0.69
N;N;.;.;.
PhyloP100
-0.17
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.050
N;N;N;N;N
REVEL
Benign
0.12
Sift
Benign
0.34
T;T;D;T;T
Sift4G
Benign
0.46
T;T;T;T;T
Polyphen
0.0
.;B;.;.;B
Vest4
0.15
MVP
0.68
MPC
0.35
ClinPred
0.031
T
GERP RS
-0.55
PromoterAI
0.011
Neutral
Varity_R
0.032
gMVP
0.38
Mutation Taster
=90/10
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: rs567683036; hg19: chr2-175629110; API