14-23382055-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_002471.4(MYH6):c.5805G>T(p.Met1935Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,870 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Uncertain significancein ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M1935T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: MYH6 NM_002471.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.50

Genes affected

MYH6 (HGNC:7576): (myosin heavy chain 6) Cardiac muscle myosin is a hexamer consisting of two heavy chain subunits, two light chain subunits, and two regulatory subunits. This gene encodes the alpha heavy chain subunit of cardiac myosin. The gene is located approximately 4kb downstream of the gene encoding the beta heavy chain subunit of cardiac myosin. Mutations in this gene cause familial hypertrophic cardiomyopathy and atrial septal defect 3. [provided by RefSeq, Feb 2017]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, MYH6
• BP4: Computational evidence support a benign effect (MetaRNN=0.18331668).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH6	NM_002471.4	c.5805G>T	p.Met1935Ile	missense_variant	39/39	ENST00000405093.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH6	ENST00000405093.9	c.5805G>T	p.Met1935Ile	missense_variant	39/39	5	NM_002471.4	P1
MYH6	ENST00000651452.1	n.1032G>T		non_coding_transcript_exon_variant	3/3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251490 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135920

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: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461870 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727248

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: 0.00000360

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000312 Hom.: 0

Bravo AF: 0.0000113

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000165 AC: 2

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hypertrophic cardiomyopathy 14 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 31, 2019

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 missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with MYH6-related conditions. This variant is present in population databases (rs372265811, ExAC 0.003%). This sequence change replaces methionine with isoleucine at codon 1935 of the MYH6 protein (p.Met1935Ile). The methionine residue is weakly conserved and there is a small physicochemical difference between methionine and isoleucine. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 02, 2022

The p.M1935I variant (also known as c.5805G>T), located in coding exon 37 of the MYH6 gene, results from a G to T substitution at nucleotide position 5805. The methionine at codon 1935 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.013	T
BayesDel_noAF	Benign	-0.24
Cadd	Benign	21
Dann	Benign	0.95
DEOGEN2	Benign	0.25	T;T
Eigen	Benign	-0.33
Eigen_PC	Benign	-0.12
FATHMM_MKL	Uncertain	0.83	D
LIST_S2	Benign	0.68	T;.
M_CAP	Benign	0.052	D
MetaRNN	Benign	0.18	T;T
MetaSVM	Benign	-0.65	T
MutationAssessor	Benign	-0.34	N;N
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.55	T
PROVEAN	Benign	0.11	N;N
REVEL	Uncertain	0.36
Sift	Benign	0.41	T;T
Sift4G	Benign	0.38	T;T
Polyphen		0.0	B;B
Vest4		0.47
MutPred		0.12		Gain of methylation at K1934 (P = 0.0845);Gain of methylation at K1934 (P = 0.0845);
MVP		0.69
MPC		0.28
ClinPred		0.24	T
GERP RS		4.4
Varity_R		0.14
gMVP		0.34

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: rs372265811; hg19: chr14-23851264;