14-23415475-ATCT-ATCTTCT

Variant names:

• chr14-23415475-A-ATCT
• rs367543052
• NM_000257.4:c.5186_5188dupAGA

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PM4_Supporting PP5

The NM_000257.4(MYH7):​c.5186_5188dupAGA​(p.Lys1729dup) variant causes a conservative inframe insertion change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: MYH7 NM_000257.4 conservative_inframe_insertion
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 0.589

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]

MHRT (HGNC:51291): (myosin heavy chain associated RNA transcript) This gene encodes a spliced long non-coding RNA that may act as a cardioprotective agent in the heart. Based on a study of a similar gene in mouse, the encoded transcript may regulate chromatin remodeling by acting as a decoy to the BRG1 chromatin repressor complex thus preventing it from binding to its genomic targets. Blocking the actions of BRG1 could be crucial in protecting the heart from pathological hypertrophy. [provided by RefSeq, Dec 2014]

ENSG00000258444 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a helix (size 38) in uniprot entity MYH7_HUMAN there are 10 pathogenic changes around while only 0 benign (100%) in NM_000257.4
• PM2: Very rare variant in population databases, with high coverage
• PM4: Nonframeshift variant in NON repetitive region in NM_000257.4. Strenght limited to Supporting due to length of the change: 1aa.
• PP5: Variant 14-23415475-A-ATCT is Pathogenic according to our data. Variant chr14-23415475-A-ATCT is described in ClinVar as [Pathogenic]. Clinvar id is 143217.Status of the report is no_assertion_criteria_provided, 0 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.5186_5188dupAGA	p.Lys1729dup	conservative_inframe_insertion	Exon 36 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.5186_5188dupAGA	p.Lys1729dup	conservative_inframe_insertion	Exon 35 of 39		NP_001393933.1
MHRT	NR_126491.1	n.36_38dupTCT		non_coding_transcript_exon_variant	Exon 1 of 6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.5186_5188dupAGA	p.Lys1729dup	conservative_inframe_insertion	Exon 36 of 40	1	NM_000257.4	ENSP00000347507.3
ENSG00000258444	ENST00000557368.1	n.126+21_126+23dupTCT		intron_variant	Intron 1 of 1	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

MYH7-related skeletal myopathy Pathogenic:1

Jan 01, 2013

Neurogenetics Laboratory, Royal Perth Hospital

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs367543052; hg19: chr14-23884684;