2-232539760-C-T

Variant names:

• chr2-232539760-C-T
• rs267606725
• NM_005199.5:c.13C>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_005199.5(CHRNG):​c.13C>T​(p.Gln5*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: CHRNG NM_005199.5 stop_gained
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:3
• Conservation: PhyloP100: 0.259
• Publications: 3 publications found

Genes affected

CHRNG (HGNC:1967): (cholinergic receptor nicotinic gamma subunit) The mammalian muscle-type acetylcholine receptor is a transmembrane pentameric glycoprotein with two alpha subunits, one beta, one delta, and one epsilon (in adult skeletal muscle) or gamma (in fetal and denervated muscle) subunit. This gene, which encodes the gamma subunit, is expressed prior to the thirty-third week of gestation in humans. The gamma subunit of the acetylcholine receptor plays a role in neuromuscular organogenesis and ligand binding and disruption of gamma subunit expression prevents the correct localization of the receptor in cell membranes. Mutations in this gene cause Escobar syndrome and a lethal form of multiple pterygium syndrome. Muscle-type acetylcholine receptor is the major antigen in the autoimmune disease myasthenia gravis.[provided by RefSeq, Sep 2009]

CHRNG Gene-Disease associations (from GenCC):

• autosomal recessive multiple pterygium syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, G2P, Orphanet
• CHRNG-associated hypo-akinesia disorder of prenatal onset

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• lethal multiple pterygium syndrome

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Orphanet
• transient neonatal myasthenia gravis

  Inheritance: AR Classification: STRONG Submitted by: Genomics England PanelApp

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 58 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-232539760-C-T is Pathogenic according to our data. Variant chr2-232539760-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 18336.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHRNG	NM_005199.5	c.13C>T	p.Gln5*	stop_gained	Exon 1 of 12	ENST00000651502.1	NP_005190.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHRNG	ENST00000651502.1	c.13C>T	p.Gln5*	stop_gained	Exon 1 of 12		NM_005199.5	ENSP00000498757.1
CHRNG	ENST00000389492.3	c.13C>T	p.Gln5*	stop_gained	Exon 1 of 11	1		ENSP00000374143.3
CHRNG	ENST00000485094.1	n.34C>T		non_coding_transcript_exon_variant	Exon 1 of 5	1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 33

Alfa AF: 0.000537 Hom.: 0

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive multiple pterygium syndrome Pathogenic:2

Dec 30, 2017

Department Of Genetics, Sultan Qaboos University Hospital, Sultan Qaboos University

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: curation

- -

Aug 01, 2006

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Scoliosis;C1837407:Ankle flexion contracture;C4025173:Arthrogryposis-like hand anomaly Pathogenic:1

Oct 16, 2019

Center for Reproductive Medicine, Peking University Third Hospital

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.0
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Benign	-0.016
Eigen_PC	Benign	-0.37
FATHMM_MKL	Benign	0.18	N
PhyloP100		0.26
Vest4		0.57
GERP RS		1.7
PromoterAI		-0.012	Neutral
Mutation Taster		=17/183	disease causing (ClinVar)

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: rs267606725; hg19: chr2-233404470;