11-77160215-G-T

Variant names:

• chr11-77160215-G-T
• rs397516282
• NM_000260.4:c.1133G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP3_Moderate

The NM_000260.4(MYO7A):​c.1133G>T​(p.Arg378Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000014 in 1,429,306 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. R378C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: MYO7A NM_000260.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.99

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 Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 11 uncertain in NM_000260.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-77160214-C-T is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.888

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MYO7A	NM_000260.4	c.1133G>T	p.Arg378Leu	missense_variant	Exon 11 of 49	ENST00000409709.9	NP_000251.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MYO7A	ENST00000409709.9	c.1133G>T	p.Arg378Leu	missense_variant	Exon 11 of 49	1	NM_000260.4	ENSP00000386331.3
MYO7A	ENST00000458637.6	c.1133G>T	p.Arg378Leu	missense_variant	Exon 11 of 49	1		ENSP00000392185.2
MYO7A	ENST00000409619.6	c.1100G>T	p.Arg367Leu	missense_variant	Exon 12 of 50	1		ENSP00000386635.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000140 AC: 2 AN: 1429306 Hom.: 0 Cov.: 31 AF XY: 0.00000141 AC XY: 1 AN XY: 707812

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: 0.0000123

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.12e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Oct 20, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 378 of the MYO7A protein (p.Arg378Leu). This variant is not present in population databases (gnomAD no frequency). 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on MYO7A protein function. 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	0.96
BayesDel_addAF	Pathogenic	0.43	D
BayesDel_noAF	Pathogenic	0.38
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	D;T;.;.
Eigen	Uncertain	0.57
Eigen_PC	Uncertain	0.61
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.88	D;D;D;D
M_CAP	Pathogenic	0.39	D
MetaRNN	Pathogenic	0.89	D;D;D;D
MetaSVM	Uncertain	0.55	D
MutationAssessor	Pathogenic	3.0	M;.;M;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-5.9	D;.;D;D
REVEL	Pathogenic	0.81
Sift	Benign	0.062	T;.;T;T
Sift4G	Uncertain	0.046	D;D;D;D
Polyphen		0.82	P;.;.;.
Vest4		0.96
MutPred		0.60		Loss of disorder (P = 0.0384);Loss of disorder (P = 0.0384);Loss of disorder (P = 0.0384);.;
MVP		0.93
MPC		0.51
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.78
gMVP		0.80

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: rs397516282; hg19: chr11-76871261;