chr14-23382056-A-AT

Variant names:

• chr14-23382056-A-AT
• rs768525215
• NM_002471.4:c.5803dupA

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PVS1_Moderate BS2

The NM_002471.4(MYH6):​c.5803dupA​(p.Met1935AsnfsTer4) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000143 in 1,614,010 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000014 (0 hom.)
• Consequence: MYH6 NM_002471.4 frameshift
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.15

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 Likely_benign. Variant got -2 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.00292 CDS is truncated, and there are 0 pathogenic variants in the truncated region.
• BS2: High AC in GnomAdExome4 at 20 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH6	NM_002471.4	c.5803dupA	p.Met1935AsnfsTer4	frameshift_variant	Exon 39 of 39	ENST00000405093.9	NP_002462.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH6	ENST00000405093.9	c.5803dupA	p.Met1935AsnfsTer4	frameshift_variant	Exon 39 of 39	5	NM_002471.4	ENSP00000386041.3
MYH6	ENST00000651452.1	n.1030dupA		non_coding_transcript_exon_variant	Exon 3 of 3

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152152 Hom.: 0 Cov.: 32

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: 0.0000441

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251488 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135918

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: 0.0000137 AC: 20 AN: 1461858 Hom.: 0 Cov.: 32 AF XY: 0.00000963 AC XY: 7 AN XY: 727236

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: 0.0000187

Gnomad4 NFE exome AF: 0.0000171

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152152 Hom.: 0 Cov.: 32 AF XY: 0.0000404 AC XY: 3 AN XY: 74320

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: 0.0000441

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.0000151

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Jan 07, 2022

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); Frameshift variant predicted to result in protein truncation as the last 5 amino acids are replaced with 3 different amino acids, although loss-of-function variants have not been reported downstream of this position in the protein; Has not been previously published as pathogenic or benign to our knowledge -

Dilated cardiomyopathy 1EE;C2750467:Hypertrophic cardiomyopathy 14 Uncertain:1

Jun 14, 2023

New York Genome Center

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.5803dup p.(Met1935AsnfsTer4) variant identified in the MYH6 gene has been deposited in the ClinVar database as a variant of uncertain significance [ClinVar ID:1695783]. The c.5803dup variant is observed in 7 alleles (~0.0011% minor allele frequency with 0 homozygotes) in population databases (gnomAD v2.1.1 and v3.1.2, TOPMed Freeze 8), suggesting it is not a common benign variant in the populations represented in those databases. The c.5803dup variant is located in the last exon of this 17-exon gene and alters the wild-type translational reading frame. The resultant mutant mRNA is predicted to escape nonsense-mediated mRNA decay. If translated, the mutant protein would lack the last 5 amino acids compared to the full length 1939 amino acid protein and instead would include 3 different amino acids p.(Met1935AsnfsTer4). Based on available evidence, this c.5803dup p.(Met1935AsnfsTer4) variant in MYH6 is reported as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

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: rs768525215; hg19: chr14-23851265;