11-77155908-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3 PP5

The NM_000260.4(MYO7A):c.287C>T(p.Thr96Met) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000113 in 1,596,774 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/23 in silico tools predict a damaging outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T96T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: MYO7A NM_000260.4 missense, splice_region
• Scores: Splicing: ADA: 0.9750
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1
• Conservation: PhyloP100: 7.55

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 6 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000260.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
• PP5: Variant 11-77155908-C-T is Pathogenic according to our data. Variant chr11-77155908-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 179974.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, Uncertain_significance=1}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYO7A	NM_000260.4	c.287C>T	p.Thr96Met	missense_variant, splice_region_variant	5/49	ENST00000409709.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYO7A	ENST00000409709.9	c.287C>T	p.Thr96Met	missense_variant, splice_region_variant	5/49	1	NM_000260.4
MYO7A	ENST00000458637.6	c.287C>T	p.Thr96Met	missense_variant, splice_region_variant	5/49	1		P1
MYO7A	ENST00000409619.6	c.254C>T	p.Thr85Met	missense_variant, splice_region_variant	6/50	1

Frequencies

GnomAD3 genomes AF: 0.0000657 AC: 10 AN: 152246 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.000193

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000130 AC: 3 AN: 230894 Hom.: 0 AF XY: 0.0000240 AC XY: 3 AN XY: 124768

Gnomad AFR exome AF: 0.0000717

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000728

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000554 AC: 8 AN: 1444528 Hom.: 0 Cov.: 31 AF XY: 0.00000559 AC XY: 4 AN XY: 716076

Gnomad4 AFR exome AF: 0.0000302

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000360

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000363

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000657 AC: 10 AN: 152246 Hom.: 0 Cov.: 33 AF XY: 0.0000807 AC XY: 6 AN XY: 74386

Gnomad4 AFR AF: 0.000193

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000142 Hom.: 0

Bravo AF: 0.0000453

ExAC AF: 0.0000165 AC: 2

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Rare genetic deafness Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Nov 05, 2014

The p.Thr96Met variant in MYO7A has been identified by our laboratory in one ind ividual with sensorineural hearing loss and retinitis pigmentosa and segregated with disease in one affected relative. Both individuals carried this variant in trans with a second pathogenic variant in MYO7A. Computational prediction tools and conservation analyses suggest that the p.Thr98Met variant may impact the pro tein, though this information is not predictive enough to determine pathogenicit y. However, the presence of this variant in combination with a reported pathogen ic variant and in an individual with hearing loss and retinitis pigmentosa, incr eases the likelihood that the p.Thr96Met variant is pathogenic. In summary, alth ough additional studies are required to fully establish its clinical significanc e, this variant is likely pathogenic. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jul 21, 2022

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 96 of the MYO7A protein (p.Thr96Met). This variant is present in population databases (rs781811444, gnomAD 0.01%). This missense change has been observed in individual(s) with non-syndromic deafness (PMID: 27344577). ClinVar contains an entry for this variant (Variation ID: 179974). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). 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	0.92
BayesDel_addAF	Pathogenic	0.31	D
BayesDel_noAF	Pathogenic	0.39
Cadd	Pathogenic	28
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;D;.;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D;D;D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Pathogenic	4.3	H;.;H;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-5.0	D;.;D;D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D;.;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		0.99	D;.;.;.
Vest4		0.99
MutPred		0.95		Gain of MoRF binding (P = 0.2767);Gain of MoRF binding (P = 0.2767);Gain of MoRF binding (P = 0.2767);.;
MVP		0.95
MPC		0.35
ClinPred		1.0	D
GERP RS		4.9
Varity_R		0.64
gMVP		0.88

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Pathogenic	0.73
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: rs781811444; hg19: chr11-76866954; COSMIC: COSV68685635;