chr14-23387550-C-G

Position:

• chr14-23387550-C-G

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2 BS2

The NM_002471.4(MYH6):​c.4629G>C​(p.Gln1543His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,754 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. Q1543K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: MYH6 NM_002471.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 1.32

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 -3 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), MYH6. . Gene score misZ 0.85843 (greater than the threshold 3.09). Trascript score misZ 4.1282 (greater than threshold 3.09). GenCC has associacion of gene with dilated cardiomyopathy, hypertrophic cardiomyopathy, Keppen-Lubinsky syndrome, atrial septal defect 3, familial isolated dilated cardiomyopathy, hypertrophic cardiomyopathy 14.
• BS2: High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH6	NM_002471.4	c.4629G>C	p.Gln1543His	missense_variant	32/39	ENST00000405093.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH6	ENST00000405093.9	c.4629G>C	p.Gln1543His	missense_variant	32/39	5	NM_002471.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461754 Hom.: 0 Cov.: 31 AF XY: 0.00000825 AC XY: 6 AN XY: 727192

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: 0.00000629

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

EpiCase AF: 0.0000545

EpiControl AF: 0.00

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

Labcorp Genetics (formerly Invitae), Labcorp

Nov 21, 2021

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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 470541). This variant has not been reported in the literature in individuals affected with MYH6-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 1543 of the MYH6 protein (p.Gln1543His). -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jul 14, 2016

The p.Q1543H variant (also known as c.4629G>C), located in coding exon 30 of the MYH6 gene, results from a G to C substitution at nucleotide position 4629. The glutamine at codon 1543 is replaced by histidine, an amino acid with highly similar properties. This variant was not reported in population-based cohorts in the following databases: Database of Single Nucleotide Polymorphisms (dbSNP), Exome Aggregation Consortium (ExAC), NHLBI Exome Sequencing Project (ESP), and 1000 Genomes Project. In the ESP, this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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	Uncertain	0.35
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.10
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.76	D;D
Eigen	Benign	0.16
Eigen_PC	Benign	0.21
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.94	D;.
M_CAP	Uncertain	0.18	D
MetaRNN	Uncertain	0.74	D;D
MetaSVM	Uncertain	0.38	D
MutationAssessor	Pathogenic	3.2	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.75	T
PROVEAN	Uncertain	-3.7	D;D
REVEL	Pathogenic	0.69
Sift	Uncertain	0.0020	D;D
Sift4G	Uncertain	0.014	D;D
Polyphen		0.029	B;B
Vest4		0.77
MutPred		0.46		Gain of catalytic residue at L1542 (P = 0.0349);Gain of catalytic residue at L1542 (P = 0.0349);
MVP		0.89
MPC		0.32
ClinPred		0.98	D
GERP RS		4.6
Varity_R		0.54
gMVP		0.57

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: rs1177280918; hg19: chr14-23856759;