14-23413770-T-G

Variant names:

• chr14-23413770-T-G
• rs767300277
• NM_000257.4:c.5779A>C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 7P and 2B. PM1 PM2 PM5 PP2 BP4_Moderate

The NM_000257.4(MYH7):​c.5779A>C​(p.Ile1927Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,216 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I1927F) has been classified as Pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: MYH7 NM_000257.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.04

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.

• PM1: In a region_of_interest Disordered (size 28) in uniprot entity MYH7_HUMAN there are 8 pathogenic changes around while only 2 benign (80%) in NM_000257.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr14-23413770-T-A is described in Lovd as [Pathogenic].
• PP2: Missense variant in the MYH7 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 341 curated pathogenic missense variants (we use a threshold of 10). The gene has 16 curated benign missense variants. Gene score misZ: 3.9329 (above the threshold of 3.09). Trascript score misZ: 6.7889 (above the threshold of 3.09). GenCC associations: The gene is linked to 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.24268293).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH7	NM_000257.4	c.5779A>C	p.Ile1927Leu	missense_variant	Exon 39 of 40	ENST00000355349.4	NP_000248.2
MYH7	NM_001407004.1	c.5779A>C	p.Ile1927Leu	missense_variant	Exon 38 of 39		NP_001393933.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH7	ENST00000355349.4	c.5779A>C	p.Ile1927Leu	missense_variant	Exon 39 of 40	1	NM_000257.4	ENSP00000347507.3

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152216 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 32

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152216 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74364

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.085
CardioboostCm	Uncertain	0.18
BayesDel_addAF	Uncertain	0.018	T
BayesDel_noAF	Benign	-0.21
CADD	Benign	20
DANN	Uncertain	0.98
DEOGEN2	Benign	0.27	T
Eigen	Benign	-0.26
Eigen_PC	Benign	-0.15
FATHMM_MKL	Uncertain	0.88	D
LIST_S2	Uncertain	0.88	D
M_CAP	Pathogenic	0.43	D
MetaRNN	Benign	0.24	T
MetaSVM	Benign	-0.44	T
MutationAssessor	Uncertain	2.7	M
PrimateAI	Benign	0.47	T
PROVEAN	Benign	-0.36	N
REVEL	Uncertain	0.30
Sift	Benign	0.35	T
Sift4G	Benign	0.77	T
Polyphen		0.019	B
Vest4		0.39
MutPred		0.13		Loss of MoRF binding (P = 0.1022);
MVP		0.83
MPC		0.58
ClinPred		0.21	T
GERP RS		5.6
Varity_R		0.10
gMVP		0.76

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: rs767300277; hg19: chr14-23882979;