17-10525330-G-T

Variant names:

• chr17-10525330-G-T
• rs138796340
• NM_017534.6:c.4556C>A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_017534.6(MYH2):​c.4556C>A​(p.Thr1519Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,828 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 (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MYH2 NM_017534.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.12

Genes affected

MYH2 (HGNC:7572): (myosin heavy chain 2) Myosins are actin-based motor proteins that function in the generation of mechanical force in eukaryotic cells. Muscle myosins are heterohexamers composed of 2 myosin heavy chains and 2 pairs of nonidentical myosin light chains. This gene encodes a member of the class II or conventional myosin heavy chains, and functions in skeletal muscle contraction. This gene is found in a cluster of myosin heavy chain genes on chromosome 17. A mutation in this gene results in inclusion body myopathy-3. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Sep 2009]

ENSG00000272736 (HGNC:):

MYHAS (HGNC:50609): (myosin heavy chain gene cluster antisense RNA) Predicted to enable primary miRNA binding activity. Predicted to be involved in response to muscle activity and skeletal muscle fiber development. Predicted to act upstream of or within with a positive effect on gene expression. Predicted to be located in cytoplasm and nucleus. [provided by Alliance of Genome Resources, Apr 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a modified_residue Phosphothreonine (size 0) in uniprot entity MYH2_HUMAN
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.891

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH2	NM_017534.6	c.4556C>A	p.Thr1519Lys	missense_variant	Exon 33 of 40	ENST00000245503.10	NP_060004.3
MYH2	NM_001100112.2	c.4556C>A	p.Thr1519Lys	missense_variant	Exon 33 of 40		NP_001093582.1
MYHAS	NR_125367.1	n.168-42207G>T		intron_variant	Intron 2 of 10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH2	ENST00000245503.10	c.4556C>A	p.Thr1519Lys	missense_variant	Exon 33 of 40	1	NM_017534.6	ENSP00000245503.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251186 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135750

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461828 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727214

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Myopathy, proximal, and ophthalmoplegia Uncertain:1

Apr 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. 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 not expected to disrupt MYH2 protein function. This variant has not been reported in the literature in individuals affected with MYH2-related conditions. This variant is present in population databases (rs138796340, gnomAD 0.006%). This sequence change replaces threonine, which is neutral and polar, with lysine, which is basic and polar, at codon 1519 of the MYH2 protein (p.Thr1519Lys). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.53
BayesDel_addAF	Uncertain	0.028	T
BayesDel_noAF	Uncertain	-0.020
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	D;D
Eigen	Pathogenic	0.90
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.80	.;T
M_CAP	Pathogenic	0.38	D
MetaRNN	Pathogenic	0.89	D;D
MetaSVM	Uncertain	0.45	D
MutationAssessor	Uncertain	2.7	M;M
PrimateAI	Pathogenic	0.85	D
PROVEAN	Uncertain	-4.0	D;D
REVEL	Pathogenic	0.72
Sift	Pathogenic	0.0	D;D
Sift4G	Uncertain	0.025	D;D
Polyphen		0.99	D;D
Vest4		0.66
MutPred		0.72		Gain of ubiquitination at T1519 (P = 0.0085);Gain of ubiquitination at T1519 (P = 0.0085);
MVP		0.97
MPC		1.0
ClinPred		0.99	D
GERP RS		5.2
Varity_R		0.86
gMVP		0.19

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs138796340; hg19: chr17-10428647; COSMIC: COSV55443052;