rs775070102

Variant names:

• chr17-7454491-A-G
• rs775070102
• NM_000747.3:c.1015A>G

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_000747.3(CHRNB1):​c.1015A>G​(p.Thr339Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000291 in 1,613,732 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 30)
  • Exomes 𝑓: 0.000030 (0 hom.)
• Consequence: CHRNB1 NM_000747.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.32
• Publications: 0 publications found

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

ENSG00000308645 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.83

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	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHRNB1	NM_000747.3	MANE Select	c.1015A>G	p.Thr339Ala	missense	Exon 8 of 11	NP_000738.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHRNB1	ENST00000306071.7	TSL:1 MANE Select	c.1015A>G	p.Thr339Ala	missense	Exon 8 of 11	ENSP00000304290.2
	CHRNB1	ENST00000536404.6	TSL:2	c.799A>G	p.Thr267Ala	missense	Exon 7 of 10	ENSP00000439209.2
	CHRNB1	ENST00000576360.1	TSL:3	c.652A>G	p.Thr218Ala	missense	Exon 7 of 10	ENSP00000459092.1

Frequencies

GnomAD3 genomes AF: 0.0000198 AC: 3 AN: 151850 Hom.: 0 Cov.: 30

Gnomad AFR AF: 0.0000242

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251470 AF XY: 0.00

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000301 AC: 44 AN: 1461882 Hom.: 0 Cov.: 33 AF XY: 0.0000330 AC XY: 24 AN XY: 727242

African (AFR) AF: 0.0000299 AC: 1 AN: 33480

American (AMR) AF: 0.00 AC: 0 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: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000378 AC: 42 AN: 1112000

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome AF: 0.0000198 AC: 3 AN: 151850 Hom.: 0 Cov.: 30 AF XY: 0.0000135 AC XY: 1 AN XY: 74156

African (AFR) AF: 0.0000242 AC: 1 AN: 41324

American (AMR) AF: 0.00 AC: 0 AN: 15234

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.00 AC: 0 AN: 5174

South Asian (SAS) AF: 0.00 AC: 0 AN: 4814

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10560

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 67970

Other (OTH) AF: 0.00 AC: 0 AN: 2080

Alfa AF: 0.0000434 Hom.: 0

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Congenital myasthenic syndrome 2A (1)
-	1	-	Inborn genetic diseases (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.51
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.060
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.67	D
Eigen	Uncertain	0.46
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Pathogenic	1.0	D
M_CAP	Benign	0.082	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Uncertain	0.51	D
MutationAssessor	Uncertain	2.7	M
PhyloP100		9.3
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.76
Sift	Uncertain	0.0080	D
Sift4G	Uncertain	0.010	D
Polyphen		0.35	B
Vest4		0.48
MutPred		0.93		Loss of disorder (P = 0.1935)
MVP		0.91
MPC		0.80
ClinPred		0.97	D
GERP RS		5.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.49
gMVP		0.85
Mutation Taster		=23/77	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs775070102; hg19: chr17-7357810;