2-232540681-T-G

Position:

• chr2-232540681-T-G

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PP3_Strong PP5_Moderate

The NM_005199.5(CHRNG):​c.320T>G​(p.Val107Gly) variant causes a missense change. 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 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:3
• Conservation: PhyloP100: 4.12

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 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.979
• PP5: Variant 2-232540681-T-G is Pathogenic according to our data. Variant chr2-232540681-T-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 18340.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr2-232540681-T-G is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHRNG	NM_005199.5	c.320T>G	p.Val107Gly	missense_variant	4/12	ENST00000651502.1	NP_005190.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHRNG	ENST00000651502.1	c.320T>G	p.Val107Gly	missense_variant	4/12		NM_005199.5	ENSP00000498757.1
CHRNG	ENST00000389492.3	c.320T>G	p.Val107Gly	missense_variant	4/11	1		ENSP00000374143.3
CHRNG	ENST00000485094.1	n.341T>G		non_coding_transcript_exon_variant	4/5	1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive multiple pterygium syndrome Pathogenic:2

Likely pathogenic, criteria provided, single submitter	research	Center for Genomic Medicine, King Faisal Specialist Hospital and Research Center	Mar 25, 2024	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Aug 01, 2006	- -

Lethal multiple pterygium syndrome Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Aug 01, 2006

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.81	D;.
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.42
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Benign	0.75	T;T
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Uncertain	0.66	D
MutationAssessor	Pathogenic	3.4	M;M
PrimateAI	Uncertain	0.48	T
PROVEAN	Pathogenic	-6.1	D;D
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		0.84	P;.
Vest4		0.81
MutPred		0.94		Loss of stability (P = 0.0161);Loss of stability (P = 0.0161);
MVP		0.82
MPC		0.50
ClinPred		0.96	D
GERP RS		4.3
Varity_R		0.98

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

Publications

LitVar

Other links and lift over

dbSNP: rs267606726; hg19: chr2-233405391;