NM_000079.4:c.540+4G>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000079.4(CHRNA1):​c.540+4G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,700 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

CHRNA1
NM_000079.4 splice_region, intron

Scores

2
Splicing: ADA: 0.0003919
2

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 0.0880

Publications

2 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: Uncertain_significance. The variant received 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.37).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CHRNA1NM_000079.4 linkc.540+4G>T splice_region_variant, intron_variant Intron 5 of 8 ENST00000348749.9 NP_000070.1 P02708-2Q53SH4
CHRNA1NM_001039523.3 linkc.615+4G>T splice_region_variant, intron_variant Intron 6 of 9 NP_001034612.1 P02708-1Q53SH4
CHRNA1XM_017003256.2 linkc.636+4G>T splice_region_variant, intron_variant Intron 5 of 8 XP_016858745.1
CHRNA1XM_017003257.2 linkc.561+4G>T splice_region_variant, intron_variant Intron 4 of 7 XP_016858746.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CHRNA1ENST00000348749.9 linkc.540+4G>T splice_region_variant, intron_variant Intron 5 of 8 1 NM_000079.4 ENSP00000261008.5 P02708-2

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251258
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
0.00000137
AC:
2
AN:
1460700
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
726662
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33450
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86206
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53388
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4984
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111848
Other (OTH)
AF:
0.00
AC:
0
AN:
60276
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
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
Cov.:
31
Alfa
AF:
0.00
Hom.:
1
Bravo
AF:
0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.37
CADD
Benign
12
DANN
Benign
0.73
PhyloP100
0.088

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00039
dbscSNV1_RF
Benign
0.048
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: rs112674580; hg19: chr2-175618943; API