17-10392567-C-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PP2 PP3 BS2

The NM_002472.3(MYH8):c.5543G>A(p.Arg1848Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000397 in 1,613,974 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 (★).

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000039 (0 hom.)
• Consequence: MYH8 NM_002472.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.04

Genes affected

MYH8 (HGNC:7578): (myosin heavy chain 8) Myosins are actin-based motor proteins that function in the generation of mechanical force in eukaryotic cells. Muscle myosins are heterohexamers composed of 2 myosin heavy chains and 2 pairs of nonidentical myosin light chains. This gene encodes a member of the class II or conventional myosin heavy chains, and functions in skeletal muscle contraction. This gene is predominantly expressed in fetal skeletal muscle. This gene is found in a cluster of myosin heavy chain genes on chromosome 17. A mutation in this gene results in trismus-pseudocamptodactyly syndrome. [provided by RefSeq, Sep 2009]

(HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PP2: Missense variant where missense usually causes diseases, MYH8
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.829
• BS2: High AC in GnomAd at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYH8	NM_002472.3	c.5543G>A	p.Arg1848Gln	missense_variant	38/40	ENST00000403437.2
MYHAS	NR_125367.1	n.76+9360C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYH8	ENST00000403437.2	c.5543G>A	p.Arg1848Gln	missense_variant	38/40	5	NM_002472.3	P1
	ENST00000399342.6	n.76+9360C>T		intron_variant, non_coding_transcript_variant		3
	ENST00000581304.1	n.52+9360C>T		intron_variant, non_coding_transcript_variant		3

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152118 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000735

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000596 AC: 15 AN: 251476 Hom.: 0 AF XY: 0.0000736 AC XY: 10 AN XY: 135916

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000867

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000435

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 0.0000390 AC: 57 AN: 1461856 Hom.: 0 Cov.: 32 AF XY: 0.0000399 AC XY: 29 AN XY: 727226

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.000134

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.000151

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000351

Gnomad4 OTH exome AF: 0.0000662

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152118 Hom.: 0 Cov.: 32 AF XY: 0.0000538 AC XY: 4 AN XY: 74314

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000193

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000735

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000965 Hom.: 0

Bravo AF: 0.0000907

TwinsUK AF: 0.00 AC: 0

ALSPAC AF: 0.000259 AC: 1

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000412 AC: 5

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hecht syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.23
BayesDel_addAF	Benign	-0.097	T
BayesDel_noAF	Uncertain	-0.040
Cadd	Pathogenic	31
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.51	D
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D
M_CAP	Benign	0.034	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	4.4	H
MutationTaster	Benign	0.99	D
PrimateAI	Uncertain	0.60	T
PROVEAN	Uncertain	-2.7	D
REVEL	Pathogenic	0.65
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.030	D
Polyphen		1.0	D
Vest4		0.74
MVP		0.93
MPC		0.84
ClinPred		0.78	D
GERP RS		5.0
Varity_R		0.64
gMVP		0.35

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: rs376732590; hg19: chr17-10295884; COSMIC: COSV67972474;