chr17-7456791-T-A

Variant names:

• chr17-7456791-T-A
• rs2302764
• NM_000747.3:c.*68T>A

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.*68T>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000693 in 1,442,716 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: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CHRNB1 NM_000747.3 3_prime_UTR
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.19
• Publications: 22 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

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=-0.8).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHRNB1	NM_000747.3	c.*68T>A		3_prime_UTR_variant	Exon 11 of 11	ENST00000306071.7	NP_000738.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHRNB1	ENST00000306071.7	c.*68T>A		3_prime_UTR_variant	Exon 11 of 11	1	NM_000747.3	ENSP00000304290.2
CHRNB1	ENST00000536404.6	c.*68T>A		3_prime_UTR_variant	Exon 10 of 10	2		ENSP00000439209.2
CHRNB1	ENST00000576360.1	c.*68T>A		3_prime_UTR_variant	Exon 10 of 10	3		ENSP00000459092.1
CHRNB1	ENST00000575379.1	c.*68T>A		3_prime_UTR_variant	Exon 2 of 2	2		ENSP00000461751.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.93e-7 AC: 1 AN: 1442716 Hom.: 0 Cov.: 26 AF XY: 0.00 AC XY: 0 AN XY: 718706

African (AFR) AF: 0.00 AC: 0 AN: 33054

American (AMR) AF: 0.00 AC: 0 AN: 44314

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25952

East Asian (EAS) AF: 0.00 AC: 0 AN: 39534

South Asian (SAS) AF: 0.00 AC: 0 AN: 85752

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52524

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

European-Non Finnish (NFE) AF: 9.12e-7 AC: 1 AN: 1096050

Other (OTH) AF: 0.00 AC: 0 AN: 59812

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	3.2
DANN	Benign	0.73
PhyloP100		-1.2

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: rs2302764; hg19: chr17-7360110;