17-7454529-G-C

Variant names:

• chr17-7454529-G-C
• rs143871421
• NM_000747.3:c.1044+9G>C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000747.3(CHRNB1):​c.1044+9G>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,062 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CHRNB1 NM_000747.3 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.447
• 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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.57).

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.1044+9G>C		intron	N/A	NP_000738.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CHRNB1	ENST00000306071.7	TSL:1 MANE Select	c.1044+9G>C		intron	N/A	ENSP00000304290.2
	CHRNB1	ENST00000536404.6	TSL:2	c.828+9G>C		intron	N/A	ENSP00000439209.2
	CHRNB1	ENST00000576360.1	TSL:3	c.681+9G>C		intron	N/A	ENSP00000459092.1

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251358 AF XY: 0.00

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: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1459062 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 725976

African (AFR) AF: 0.00 AC: 0 AN: 33416

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.00 AC: 0 AN: 86202

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53402

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5724

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1109510

Other (OTH) AF: 0.00 AC: 0 AN: 60284

GnomAD4 genome Cov.: 30

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.57
CADD	Benign	11
DANN	Benign	0.83
PhyloP100		0.45

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

Other links and lift over

dbSNP: rs143871421; hg19: chr17-7357848;