rs876657708

Positions:

• chr17-18159680-G-T

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1 PM2 PP3_Strong PP5_Very_Strong

The NM_016239.4(MYO15A):​c.9303+1G>T variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: MYO15A NM_016239.4 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 9.89

Genes affected

MYO15A (HGNC:7594): (myosin XVA) This gene encodes an unconventional myosin. This protein differs from other myosins in that it has a long N-terminal extension preceding the conserved motor domain. Studies in mice suggest that this protein is necessary for actin organization in the hair cells of the cochlea. Mutations in this gene have been associated with profound, congenital, neurosensory, nonsyndromal deafness. This gene is located within the Smith-Magenis syndrome region on chromosome 17. Read-through transcripts containing an upstream gene and this gene have been identified, but they are not thought to encode a fusion protein. Several alternatively spliced transcript variants have been described, but their full length sequences have not been determined. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 22 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-18159680-G-T is Pathogenic according to our data. Variant chr17-18159680-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 228374.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
MYO15A	NM_016239.4	c.9303+1G>T		splice_donor_variant		ENST00000647165.2
MYO15A	XM_017024714.3	c.9243+1G>T		splice_donor_variant
MYO15A	XM_017024715.3	c.9306+1G>T		splice_donor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
MYO15A	ENST00000647165.2	c.9303+1G>T		splice_donor_variant			NM_016239.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461872 Hom.: 0 Cov.: 33 AF XY: 0.00000413 AC XY: 3 AN XY: 727242

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: 0.00000360

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000712 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Nov 18, 2021

DNA sequence analysis of the MYO15A gene demonstrated a sequence change in the canonical splice donor site of intron 55, c.9303+1G>T. This sequence change is predicted to disrupt the canonical splice donor site, and affect normal splicing of exon 55. The c.9303+1G>T change has not been previously described in individual with MYO15A-related disorder. This sequence change has not been described in the gnomAD population database. Collectively, this evidence suggests c.9303+1G>T is likely pathogenic, however, functional studies have not been performed to prove this conclusively. -

Rare genetic deafness Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jun 16, 2015

The c.9303+1G>T variant in MYO15A has not been previously reported in individual s with hearing loss and was absent from large population studies. This variant o ccurs in the invariant region (+/- 1/2) of the splice consensus sequence and is predicted to cause altered splicing leading to an abnormal or absent protein. Lo ss-of-function variants in the MYO15A gene are an established disease mechanism for autosomal recessive hearing loss. In summary, this variant meets our criteri a to be classified as pathogenic for hearing loss in an autosomal recessive mann er (www.partners.org/personalizedmedicine/lmm), based on the predicted impact of the variant. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D
GERP RS		5.6

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.63		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.63		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs876657708; hg19: chr17-18062994;