rs181652070

Positions:

• chr9-110787758-C-G
• chr9-110787758-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_005592.4(MUSK):​c.1847C>G​(p.Ser616Trp) variant causes a missense change involving the alteration of a 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: MUSK NM_005592.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.57

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 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.88

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MUSK	NM_005592.4	c.1847C>G	p.Ser616Trp	missense_variant	14/15	ENST00000374448.9	NP_005583.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MUSK	ENST00000374448.9	c.1847C>G	p.Ser616Trp	missense_variant	14/15	5	NM_005592.4	ENSP00000363571	P4
MUSK	ENST00000416899.7	c.1823C>G	p.Ser608Trp	missense_variant	13/14	5		ENSP00000393608	A1
MUSK	ENST00000189978.10	c.1589C>G	p.Ser530Trp	missense_variant	13/14	5		ENSP00000189978
MUSK	ENST00000374438.1	n.878C>G		non_coding_transcript_exon_variant	3/3	3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

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

Labcorp Genetics (formerly Invitae), Labcorp

Aug 21, 2019

This sequence change replaces serine with tryptophan at codon 616 of the MUSK protein (p.Ser616Trp). The serine residue is highly conserved and there is a large physicochemical difference between serine and tryptophan. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with MUSK-related conditions. This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.76
BayesDel_addAF	Pathogenic	0.28	D
BayesDel_noAF	Pathogenic	0.16
CADD	Pathogenic	33
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.70	D;.;.;.
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;D
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.88	D;D;D;D
MetaSVM	Uncertain	0.56	D
MutationAssessor	Uncertain	2.7	M;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-5.9	D;.;.;.
REVEL	Pathogenic	0.79
Sift	Pathogenic	0.0	D;.;.;.
Sift4G	Pathogenic	0.0010	D;D;D;D
Polyphen		1.0	D;.;.;.
Vest4		0.74
MutPred		0.62		Loss of disorder (P = 6e-04);.;.;.;
MVP		0.95
MPC		0.81
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.92
gMVP		0.80

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: rs181652070; hg19: chr9-113550038;