rs397516777

chr14-23404785-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PP2 PP3_Moderate

The NM_002471.4(MYH6):c.568C>T(p.Arg190Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000041 in 1,461,884 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R190H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: MYH6 NM_002471.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.851

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 3 ACMG points.

• PP2: Missense variant where missense usually causes diseases, MYH6
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.892

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH6	NM_002471.4	c.568C>T	p.Arg190Cys	missense_variant	7/39	ENST00000405093.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH6	ENST00000405093.9	c.568C>T	p.Arg190Cys	missense_variant	7/39	5	NM_002471.4	P1
MYH6	ENST00000557461.2	n.635C>T		non_coding_transcript_exon_variant	7/14	5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000795 AC: 2 AN: 251484 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135916

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: 0.00000410 AC: 6 AN: 1461884 Hom.: 0 Cov.: 33 AF XY: 0.00000413 AC XY: 3 AN XY: 727244

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jun 10, 2015

The p.Arg190Cys variant in MYH6 not been identified in any other families with c ardiomyopathy, but has been identified in 2/66728 European chromosomes by the Ex ome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs397516 777). Computational prediction tools and conservation analysis suggest that the p.Arg190Cys variant may impact the protein, though this information is not predi ctive enough to determine pathogenicity. In summary, the clinical significance o f the p.Arg190Cys variant is uncertain. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 04, 2023

The c.568C>T (p.R190C) alteration is located in exon 7 (coding exon 5) of the MYH6 gene. This alteration results from a C to T substitution at nucleotide position 568, causing the arginine (R) at amino acid position 190 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	0.0
Cadd	Pathogenic	34
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.83	D;D
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.95	D;.
M_CAP	Uncertain	0.18	D
MetaRNN	Pathogenic	0.89	D;D
MetaSVM	Uncertain	0.37	D
MutationAssessor	Uncertain	2.9	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.92	D
PROVEAN	Pathogenic	-5.6	D;D
REVEL	Pathogenic	0.78
Sift	Uncertain	0.0060	D;D
Sift4G	Uncertain	0.0050	D;D
Polyphen		1.0	D;D
Vest4		0.89
MutPred		0.62		Gain of catalytic residue at K189 (P = 0);Gain of catalytic residue at K189 (P = 0);
MVP		0.87
MPC		1.3
ClinPred		0.97	D
GERP RS		3.3
Varity_R		0.42
gMVP		0.83

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs397516777; hg19: chr14-23873994;