NM_002471.4:c.3346C>G

Variant names:

• chr14-23390443-G-C
• rs372446459
• NM_002471.4:c.3346C>G

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_002471.4(MYH6):​c.3346C>G​(p.Arg1116Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,540 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/24 in silico tools predict a damaging 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. R1116H) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYH6 NM_002471.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.74
• Publications: 0 publications found

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]

MYH6 Gene-Disease associations (from GenCC):

• hypertrophic cardiomyopathy 14

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Laboratory for Molecular Medicine
• Keppen-Lubinsky syndrome

  Inheritance: AD Classification: MODERATE Submitted by: Illumina
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• atrial septal defect 3

  Inheritance: AD Classification: LIMITED Submitted by: G2P
• dilated cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• hypertrophic cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYH6	NM_002471.4	c.3346C>G	p.Arg1116Gly	missense_variant	Exon 26 of 39	ENST00000405093.9	NP_002462.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYH6	ENST00000405093.9	c.3346C>G	p.Arg1116Gly	missense_variant	Exon 26 of 39	5	NM_002471.4	ENSP00000386041.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460540 Hom.: 0 Cov.: 35 AF XY: 0.00000275 AC XY: 2 AN XY: 726640

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44698

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26112

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86220

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52318

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5726

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111928

Other (OTH) AF: 0.00 AC: 0 AN: 60364

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Dec 02, 2020

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R1116G variant (also known as c.3346C>G), located in coding exon 24 of the MYH6 gene, results from a C to G substitution at nucleotide position 3346. The arginine at codon 1116 is replaced by glycine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious 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	Pathogenic	0.82
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.36
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.81	D;D
Eigen	Pathogenic	0.80
Eigen_PC	Uncertain	0.62
LIST_S2	Uncertain	0.95	D;.
M_CAP	Pathogenic	0.53	D
MetaRNN	Pathogenic	0.93	D;D
MetaSVM	Pathogenic	0.86	D
MutationAssessor	Pathogenic	3.0	M;M
PhyloP100		9.7
PrimateAI	Pathogenic	0.79	T
PROVEAN	Pathogenic	-5.2	D;D
Sift	Pathogenic	0.0	D;D
Sift4G	Uncertain	0.012	D;D
Vest4		0.88
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.63
gMVP		0.70
Mutation Taster		=12/88	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.74		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.74		Position offset: -1

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

Other links and lift over

dbSNP: rs372446459; hg19: chr14-23859652;