11-77179855-C-A

Position:

• chr11-77179855-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000260.4(MYO7A):​c.2488C>A​(p.Arg830Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0000151 in 1,389,642 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. R830H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: MYO7A NM_000260.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.03

Genes affected

MYO7A (HGNC:7606): (myosin VIIA) This gene is a member of the myosin gene family. Myosins are mechanochemical proteins characterized by the presence of a motor domain, an actin-binding domain, a neck domain that interacts with other proteins, and a tail domain that serves as an anchor. This gene encodes an unconventional myosin with a very short tail. Defects in this gene are associated with the mouse shaker-1 phenotype and the human Usher syndrome 1B which are characterized by deafness, reduced vestibular function, and (in human) retinal degeneration. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYO7A	NM_000260.4	c.2488C>A	p.Arg830Ser	missense_variant	21/49	ENST00000409709.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYO7A	ENST00000409709.9	c.2488C>A	p.Arg830Ser	missense_variant	21/49	1	NM_000260.4

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000718 AC: 1 AN: 139192 Hom.: 0 AF XY: 0.0000133 AC XY: 1 AN XY: 75372

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: 0.0000188

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000151 AC: 21 AN: 1389642 Hom.: 0 Cov.: 31 AF XY: 0.0000131 AC XY: 9 AN XY: 685792

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: 0.0000185

Gnomad4 OTH exome AF: 0.0000173

GnomAD4 genome Cov.: 34

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 22, 2022

This sequence change replaces arginine, which is basic and polar, with serine, which is neutral and polar, at codon 830 of the MYO7A protein (p.Arg830Ser). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with MYO7A-related conditions. 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 expected to disrupt MYO7A protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.88
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	35
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.48	T;T;.;.;.;D
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D;D;D
M_CAP	Pathogenic	0.68	D
MetaRNN	Pathogenic	0.90	D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.9	H;.;H;.;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-5.8	D;.;D;D;.;D
REVEL	Pathogenic	0.84
Sift	Pathogenic	0.0	D;.;D;D;.;T
Sift4G	Uncertain	0.0020	D;D;D;D;.;T
Polyphen		1.0	D;.;.;.;.;.
Vest4		0.92
MutPred		0.65		Loss of methylation at R830 (P = 0.0308);Loss of methylation at R830 (P = 0.0308);Loss of methylation at R830 (P = 0.0308);.;.;.;
MVP		0.98
MPC		0.49
ClinPred		1.0	D
GERP RS		5.4
Varity_R		0.97
gMVP		0.85

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.65		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.65		Position offset: -4

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs797044493; hg19: chr11-76890901;