14-23419284-G-C

Position:

• chr14-23419284-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP2 PP3_Moderate

The ENST00000355349.4(MYH7):​c.3865C>G​(p.Arg1289Gly) variant causes a missense change involving the alteration of a non-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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1289Q) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYH7 ENST00000355349.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.233

Genes affected

MYH7 (HGNC:7577): (myosin heavy chain 7) Muscle myosin is a hexameric protein containing 2 heavy chain subunits, 2 alkali light chain subunits, and 2 regulatory light chain subunits. This gene encodes the beta (or slow) heavy chain subunit of cardiac myosin. It is expressed predominantly in normal human ventricle. It is also expressed in skeletal muscle tissues rich in slow-twitch type I muscle fibers. Changes in the relative abundance of this protein and the alpha (or fast) heavy subunit of cardiac myosin correlate with the contractile velocity of cardiac muscle. Its expression is also altered during thyroid hormone depletion and hemodynamic overloading. Mutations in this gene are associated with familial hypertrophic cardiomyopathy, myosin storage myopathy, dilated cardiomyopathy, and Laing distal myopathy. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Uncertain_significance. Variant got 5 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), MYH7. . Gene score misZ 3.9329 (greater than the threshold 3.09). Trascript score misZ 6.7889 (greater than threshold 3.09). GenCC has associacion of gene with hyaline body myopathy, MYH7-related skeletal myopathy, dilated cardiomyopathy 1S, congenital myopathy 7A, myosin storage, autosomal dominant, dilated cardiomyopathy, left ventricular noncompaction, myopathy, myosin storage, autosomal dominant, hypertrophic cardiomyopathy, congenital heart disease, Ebstein anomaly, arrhythmogenic right ventricular cardiomyopathy, myopathy, myosin storage, autosomal recessive, hypertrophic cardiomyopathy 1, familial isolated dilated cardiomyopathy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.879

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYH7	NM_000257.4	c.3865C>G	p.Arg1289Gly	missense_variant	29/40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.3865C>G	p.Arg1289Gly	missense_variant	28/39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.3865C>G	p.Arg1289Gly	missense_variant	29/40	1	NM_000257.4	ENSP00000347507	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hypertrophic cardiomyopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 03, 2021

A computational algorithm designed to assess the pathogenicity of variants in MYH7 with regard to hypertrophic cardiomyopathy predicted this sequence change to be deleterious. The algorithm has a sensitivity of 94% and a specificity of 89% (PMID: 21310275). In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a MYH7-related disease. This sequence change replaces arginine with glycine at codon 1289 of the MYH7 protein (p.Arg1289Gly). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and glycine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.58
CardioboostCm	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.83	D
Eigen	Uncertain	0.23
Eigen_PC	Benign	0.049
FATHMM_MKL	Benign	0.18	N
LIST_S2	Benign	0.82	T
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Pathogenic	3.0	M
MutationTaster	Benign	0.88	D
PrimateAI	Uncertain	0.68	T
PROVEAN	Pathogenic	-5.1	D
REVEL	Pathogenic	0.70
Sift	Pathogenic	0.0	D
Sift4G	Benign	0.068	T
Polyphen		1.0	D
Vest4		0.86
MutPred		0.59		Gain of catalytic residue at L1287 (P = 0.0824);
MVP		0.91
MPC		1.3
ClinPred		0.99	D
GERP RS		2.0
Varity_R		0.70
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: rs180824037; hg19: chr14-23888493;