rs551520537

chr9-110800821-G-Achr9-110800821-G-Cchr9-110800821-G-T

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_005592.4(MUSK):c.2443G>A(p.Val815Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000822 in 1,460,432 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V815L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000082 (0 hom.)
• Consequence: MUSK NM_005592.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 10.0

Genes affected

MUSK (HGNC:7525): (muscle associated receptor tyrosine kinase) This gene encodes a muscle-specific tyrosine kinase receptor. The encoded protein may play a role in clustering of the acetylcholine receptor in the postsynaptic neuromuscular junction. Mutations in this gene have been associated with congenital myasthenic syndrome. Alternatively spliced transcript variants have been described.[provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.75

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MUSK	NM_005592.4	c.2443G>A	p.Val815Met	missense_variant	15/15	ENST00000374448.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MUSK	ENST00000374448.9	c.2443G>A	p.Val815Met	missense_variant	15/15	5	NM_005592.4	P4
MUSK	ENST00000416899.7	c.2419G>A	p.Val807Met	missense_variant	14/14	5		A1
MUSK	ENST00000189978.10	c.2185G>A	p.Val729Met	missense_variant	14/14	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000242 AC: 6 AN: 248308 Hom.: 0 AF XY: 0.0000297 AC XY: 4 AN XY: 134596

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000223

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000890

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000822 AC: 12 AN: 1460432 Hom.: 0 Cov.: 32 AF XY: 0.00000964 AC XY: 7 AN XY: 726262

Gnomad4 AFR exome AF: 0.0000299

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000126

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.0000113

ExAC AF: 0.0000248 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Fetal akinesia deformation sequence 1;C4225368:Congenital myasthenic syndrome 9 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Sep 01, 2021

This sequence change replaces valine with methionine at codon 815 of the MUSK protein (p.Val815Met). The valine residue is highly conserved and there is a small physicochemical difference between valine and methionine. This variant is present in population databases (rs551520537, ExAC 0.02%). This variant has not been reported in the literature in individuals affected with MUSK-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt MUSK protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.63
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Pathogenic	0.23
Cadd	Pathogenic	32
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.44	T;.;.;.
Eigen	Pathogenic	0.92
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D
M_CAP	Uncertain	0.20	D
MetaRNN	Pathogenic	0.75	D;D;D;D
MetaSVM	Uncertain	0.59	D
MutationAssessor	Benign	1.5	L;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Benign	-2.2	N;.;.;.
REVEL	Pathogenic	0.74
Sift	Uncertain	0.0010	D;.;.;.
Sift4G	Uncertain	0.0030	D;D;D;D
Polyphen		1.0	D;.;.;.
Vest4		0.88
MutPred		0.51		Gain of catalytic residue at V811 (P = 0.0399);.;.;.;
MVP		0.87
MPC		0.69
ClinPred		0.61	D
GERP RS		5.6
Varity_R		0.64
gMVP		0.82

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: rs551520537; hg19: chr9-113563101; COSMIC: COSV51877474;