chr11-72106051-C-T

Position:

• chr11-72106051-C-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_001393500.2(TOMT):​c.100C>T​(p.Arg34*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000858 in 1,398,510 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 Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000086 (0 hom.)
• Consequence: TOMT NM_001393500.2 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.60

Genes affected

TOMT (HGNC:55527): (transmembrane O-methyltransferase) This gene encodes a catechol-O-methyltransferase that catalyzes the transfer of a methyl group from S-adenosyl-L-methionine to a hydroxyl group of catechols and is essential for auditory and vestibular function. Mutations in this gene have been associated with nonsyndromic deafness. Readthrough transcription is observed across this gene and the adjacent leucine-rich repeat containing 51 gene. A third locus (GeneID:220074) is defined to represent the readthrough transcripts. [provided by RefSeq, Feb 2021]

LRTOMT (HGNC:25033): (leucine rich transmembrane and O-methyltransferase domain containing) This locus represents naturally occurring readthrough transcription between the neighboring LRRC51 (leucine-rich repeat containing 51) and TOMT (transmembrane O-methyltransferase) genes on chromosome 11. The readthrough transcript encodes a fusion protein that shares sequence identity with each individual gene product. Multiple reports implicate mutations in this gene in nonsyndromic deafness.[provided by RefSeq, Feb 2021]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-72106051-C-T is Pathogenic according to our data. Variant chr11-72106051-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 1804950.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TOMT	NM_001393500.2	c.100C>T	p.Arg34*	stop_gained	1/3	ENST00000541899.3	NP_001380429.1
LRTOMT	NM_001145308.5	c.199C>T	p.Arg67*	stop_gained	5/7		NP_001138780.1
LRTOMT	NM_001145309.4	c.199C>T	p.Arg67*	stop_gained	7/9		NP_001138781.1
LRTOMT	NM_001145310.4	c.84-5C>T		splice_region_variant, intron_variant			NP_001138782.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TOMT	ENST00000541899.3	c.100C>T	p.Arg34*	stop_gained	1/3	5	NM_001393500.2	ENSP00000494667.1
LRTOMT	ENST00000307198.11	c.199C>T	p.Arg67*	stop_gained	5/7	2		ENSP00000305742.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000647 AC: 1 AN: 154444 Hom.: 0 AF XY: 0.0000122 AC XY: 1 AN XY: 82034

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: 0.0000439

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000858 AC: 12 AN: 1398510 Hom.: 0 Cov.: 31 AF XY: 0.0000116 AC XY: 8 AN XY: 689828

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000560

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000112

Gnomad4 SAS exome AF: 0.0000252

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000371

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.0000388 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive nonsyndromic hearing loss 63 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

May 06, 2021

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with deafness (MIM#611451). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0201 - Variant is predicted to cause nonsense-mediated decay (NMD) and loss of protein (premature termination codon is located at least 54 nucleotides upstream of the final exon-exon junction). (SP) 0219 - This variant is non-coding in an alternative transcript. This gene encodes two structurally unrelated proteins, LRTOMT1 and LRTOMT2 (PMID: 18953341). This variant is non-coding in LRTOMT1. (I) 0252 - This variant is homozygous. (I) 0304 - Variant is present in gnomAD <0.01 for a recessive condition (1 heterozygote, 0 homozygotes). (SP) 0702 - Other NMD-predicted variants comparable to the one identified in this case have strong previous evidence for pathogenicity. NMD-predicted variants have been reported in multiple individuals with autosomal recessive deafness (ClinVar, PMID: 18953341, 18794526, 21739586). (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	36
DANN	Uncertain	1.0
Eigen	Uncertain	0.43
Eigen_PC	Benign	0.22
FATHMM_MKL	Benign	0.76	D
Vest4		0.31
GERP RS		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs780468292; hg19: chr11-71817097;