chr6-75832920-A-G

Variant names:

• chr6-75832920-A-G
• rs397517053
• NM_004999.4:c.470A>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_004999.4(MYO6):​c.470A>G​(p.Lys157Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: MYO6 NM_004999.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.87
• Publications: 5 publications found

Genes affected

MYO6 (HGNC:7605): (myosin VI) This gene encodes a reverse-direction motor protein that moves toward the minus end of actin filaments and plays a role in intracellular vesicle and organelle transport. The protein consists of a motor domain containing an ATP- and an actin-binding site and a globular tail which interacts with other proteins. This protein maintains the structural integrity of inner ear hair cells and mutations in this gene cause non-syndromic autosomal dominant and recessive hearing loss. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2014]

MYO6 Gene-Disease associations (from GenCC):

• autosomal dominant nonsyndromic hearing loss 22

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), PanelApp Australia
• nonsyndromic genetic hearing loss

  Inheritance: AD, AR Classification: DEFINITIVE, MODERATE Submitted by: ClinGen, G2P
• autosomal recessive nonsyndromic hearing loss 37

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Ambry Genetics
• autosomal dominant nonsyndromic hearing loss

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive sensorineural hearing loss-hypertrophic cardiomyopathy syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.912

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004999.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYO6	NM_004999.4	MANE Select	c.470A>G	p.Lys157Arg	missense	Exon 6 of 35	NP_004990.3
	MYO6	NM_001368865.1		c.470A>G	p.Lys157Arg	missense	Exon 6 of 36	NP_001355794.1
	MYO6	NM_001368866.1		c.470A>G	p.Lys157Arg	missense	Exon 6 of 35	NP_001355795.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MYO6	ENST00000369977.8	TSL:1 MANE Select	c.470A>G	p.Lys157Arg	missense	Exon 6 of 35	ENSP00000358994.3
	MYO6	ENST00000615563.4	TSL:1	c.470A>G	p.Lys157Arg	missense	Exon 5 of 32	ENSP00000478013.1
	MYO6	ENST00000664640.1		c.470A>G	p.Lys157Arg	missense	Exon 6 of 36	ENSP00000499278.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Sep 10, 2018

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Lys157Arg variant in MYO6 has been previously reported by our laboratory i n 1 individual with hearing loss and was absent from large population studies. Computational prediction tools and conservation analysis suggest that this varia nt may impact the protein, though this information is not predictive enough to d etermine pathogenicity. In addition, this variant is referred to in several func tional studies as the "K157R rigor mutant" and has been used in several function al studies because of its "rigor-like" actin binding, whereby it exhibits an inc reased binding affinity to actin (Arden 2016, Aschenbrenner 2004, Kruppa 2018, M asters 2017, Masters 2017, Waxse 2017), and shows no movement of vesicles along actin filaments (Aschenbrenner 2004). These in vitro functional studies suggest that the variant alters normal protein function, however, these types of assays may not accurately represent biological function. In summary, the clinical signi ficance of the p.Lys157Arg variant is uncertain. ACMG/AMP criteria applied: PM2, PS3_Supporting, PP3.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.98
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.51
CADD	Uncertain	26
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.89	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.42	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.5	H
PhyloP100		8.9
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-2.9	D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.59		Loss of ubiquitination at K157 (P = 0.0107)
MVP		0.97
MPC		0.21
ClinPred		1.0	D
GERP RS		5.5
gMVP		0.95
Mutation Taster		=15/85	disease causing

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

Other links and lift over

dbSNP: rs397517053; hg19: chr6-76542637;