14-23404352-C-T

Position:

chr14-23404352-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2BS2

The NM_002471.4(MYH6):c.679G>A(p.Ala227Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000186 in 1,614,220 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

MYH6
NM_002471.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 0.252

Variant links:

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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 GnomAd4 at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MYH6	NM_002471.4 linkuse as main transcript	c.679G>A	p.Ala227Thr	missense_variant	8/39	ENST00000405093.9	NP_002462.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MYH6	ENST00000405093.9 linkuse as main transcript	c.679G>A	p.Ala227Thr	missense_variant	8/39	5	NM_002471.4	ENSP00000386041	P1
MYH6	ENST00000557461.2 linkuse as main transcript	n.746G>A		non_coding_transcript_exon_variant	8/14	5

Frequencies

GnomAD3 genomes

AF:

0.0000723

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000523

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:

0.00

Gnomad OTH

AF:

0.00143

GnomAD3 exomes

AF:

0.0000278

AC:

AN:

251486

Hom.:

AF XY:

0.0000294

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000131

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461884

Hom.:

Cov.:

AF XY:

0.0000151

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.000104

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.0000722

AC:

AN:

152336

Hom.:

Cov.:

AF XY:

0.0000671

AC XY:

AN XY:

74480

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000523

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00142

Alfa

AF:

0.0000699

Hom.:

Bravo

AF:

0.000208

TwinsUK

AF:

0.00

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jun 14, 2013

The Ala227Thr variant in MYH6 has not been reported in individuals with cardiomy opathy, but has been identified in 1.8% (2/110) of Puerto Rican chromosomes by t he 1000 Genomes Project (dbSNP rs201828188). Computational analyses (biochemical amino acid properties, conservation, AlignGVGD, PolyPhen2, and SIFT) do not pro vide strong support for or against an impact to the protein. The presence of thi s variant in the general population raises the possibility that it may be benign but this additional information is needed to establish this with confidence -

Hypertrophic cardiomyopathy 14

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 06, 2022

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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt MYH6 protein function. ClinVar contains an entry for this variant (Variation ID: 164254). This missense change has been observed in individual(s) with dilated cardiomyopathy (PMID: 32746448). This variant is present in population databases (rs201828188, gnomAD 0.01%). This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 227 of the MYH6 protein (p.Ala227Thr). -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 31, 2022

The p.A227T variant (also known as c.679G>A), located in coding exon 6 of the MYH6 gene, results from a G to A substitution at nucleotide position 679. The alanine at codon 227 is replaced by threonine, an amino acid with similar properties. This variant was reported in one individual from a pediatric dilated cardiomyopathy (DCM) cohort; however, clinical details were limited (Burstein DS et al. Pediatr Res, 2021 05;89:1470-1476). This variant was also described in a child with progeroid features with no known cardiac findings, who had additional co-occurring de novo variants also detected on exome analysis (Hernandez-Hernandez C et al. AME Case Rep, 2021 Oct;5:40). 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

Pathogenic

0.69

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.24

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.77

D;D

Eigen

Uncertain

0.33

Eigen_PC

Benign

0.16

FATHMM_MKL

Benign

0.42

LIST_S2

Benign

0.57

T;.

M_CAP

Uncertain

0.14

MetaRNN

Uncertain

0.63

D;D

MetaSVM

Uncertain

0.0081

MutationAssessor

Uncertain

2.6

M;M

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.73

PROVEAN

Benign

-1.7

N;N

REVEL

Uncertain

0.36

Sift

Uncertain

0.0080

D;D

Sift4G

Uncertain

0.015

D;D

Polyphen

1.0

D;D

Vest4

0.72

MVP

0.74

MPC

1.1

ClinPred

0.31

GERP RS

3.4

Varity_R

0.34

gMVP

0.77

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over