17-10521320-T-C

Position:

• chr17-10521320-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_017534.6(MYH2):​c.5786A>G​(p.Lys1929Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,838 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • 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: 6.27

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]

(HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), MYH2. . Gene score misZ 1.9724 (greater than the threshold 3.09). Trascript score misZ 4.733 (greater than threshold 3.09). GenCC has associacion of gene with childhood-onset autosomal recessive myopathy with external ophthalmoplegia, hereditary inclusion body myopathy-joint contractures-ophthalmoplegia syndrome, myopathy, proximal, and ophthalmoplegia.
• BP4: Computational evidence support a benign effect (MetaRNN=0.302802).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH2	NM_017534.6	c.5786A>G	p.Lys1929Arg	missense_variant	40/40	ENST00000245503.10
MYHAS	NR_125367.1	n.168-46217T>C		intron_variant, non_coding_transcript_variant
MYH2	NM_001100112.2	c.5786A>G	p.Lys1929Arg	missense_variant	40/40

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH2	ENST00000245503.10	c.5786A>G	p.Lys1929Arg	missense_variant	40/40	1	NM_017534.6	P1
	ENST00000399342.6	n.207-12004T>C		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251454 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135894

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461838 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727222

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Myopathy, proximal, and ophthalmoplegia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 22, 2019

Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C25"). This variant has not been reported in the literature in individuals with MYH2-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces lysine with arginine at codon 1929 of the MYH2 protein (p.Lys1929Arg). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and arginine. 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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site, but this prediction has not been confirmed by published transcriptional studies. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.093
BayesDel_addAF	Uncertain	0.16	D
BayesDel_noAF	Uncertain	0.010
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.15	.;T;T;.
Eigen	Uncertain	0.35
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Benign	0.83	.;.;T;T
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.30	T;T;T;T
MetaSVM	Uncertain	-0.061	T
MutationAssessor	Benign	1.2	.;L;L;.
MutationTaster	Benign	0.67	D;D;D
PrimateAI	Uncertain	0.72	T
PROVEAN	Benign	-0.59	N;N;N;.
REVEL	Benign	0.22
Sift	Pathogenic	0.0	D;T;T;.
Sift4G	Benign	0.15	T;T;T;T
Polyphen		0.19	.;B;B;.
Vest4		0.29
MutPred		0.50		.;Loss of ubiquitination at K1929 (P = 0.063);Loss of ubiquitination at K1929 (P = 0.063);.;
MVP		0.85
MPC		0.45
ClinPred		0.62	D
GERP RS		5.5
Varity_R		0.18
gMVP		0.095

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: rs1197611302; hg19: chr17-10424637;