rs188185141

Variant names:

• chr2-178597640-T-C
• rs188185141
• NM_001267550.2:c.57442A>G

Your query was ambiguous. Multiple possible variants found:

• chr2-178597640-T-C
• chr2-178597640-T-G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP6

The NM_001267550.2(TTN):​c.57442A>G​(p.Met19148Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000666 in 1,613,262 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 15/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00039 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00069 (1 hom.)
• Consequence: TTN NM_001267550.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10 B:14
• Conservation: PhyloP100: 1.89
• Publications: 7 publications found

Genes affected

TTN (HGNC:12403): (titin) This gene encodes a large abundant protein of striated muscle. The product of this gene is divided into two regions, a N-terminal I-band and a C-terminal A-band. The I-band, which is the elastic part of the molecule, contains two regions of tandem immunoglobulin domains on either side of a PEVK region that is rich in proline, glutamate, valine and lysine. The A-band, which is thought to act as a protein-ruler, contains a mixture of immunoglobulin and fibronectin repeats, and possesses kinase activity. An N-terminal Z-disc region and a C-terminal M-line region bind to the Z-line and M-line of the sarcomere, respectively, so that a single titin molecule spans half the length of a sarcomere. Titin also contains binding sites for muscle associated proteins so it serves as an adhesion template for the assembly of contractile machinery in muscle cells. It has also been identified as a structural protein for chromosomes. Alternative splicing of this gene results in multiple transcript variants. Considerable variability exists in the I-band, the M-line and the Z-disc regions of titin. Variability in the I-band region contributes to the differences in elasticity of different titin isoforms and, therefore, to the differences in elasticity of different muscle types. Mutations in this gene are associated with familial hypertrophic cardiomyopathy 9, and autoantibodies to titin are produced in patients with the autoimmune disease scleroderma. [provided by RefSeq, Feb 2012]

TTN-AS1 (HGNC:44124): (TTN antisense RNA 1) This gene encodes a non-coding RNA transcribed from the opposite strand to the titin gene. [provided by RefSeq, Aug 2016]

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.029392332).
• BP6: Variant 2-178597640-T-C is Benign according to our data. Variant chr2-178597640-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 191935.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001267550.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	NM_001267550.2	MANE Select	c.57442A>G	p.Met19148Val	missense	Exon 294 of 363	NP_001254479.2
	TTN	NM_001256850.1		c.52519A>G	p.Met17507Val	missense	Exon 244 of 313	NP_001243779.1
	TTN	NM_133378.4		c.49738A>G	p.Met16580Val	missense	Exon 243 of 312	NP_596869.4

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	TTN	ENST00000589042.5	TSL:5 MANE Select	c.57442A>G	p.Met19148Val	missense	Exon 294 of 363	ENSP00000467141.1
	TTN	ENST00000446966.2	TSL:1	c.57286A>G	p.Met19096Val	missense	Exon 292 of 361	ENSP00000408004.2
	TTN	ENST00000436599.2	TSL:1	c.57166A>G	p.Met19056Val	missense	Exon 292 of 361	ENSP00000405517.2

Frequencies

GnomAD3 genomes AF: 0.000395 AC: 60 AN: 152048 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000584

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.000188

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000706

Gnomad OTH AF: 0.000478

GnomAD2 exomes AF: 0.000496 AC: 123 AN: 248042 AF XY: 0.000461

Gnomad AFR exome AF: 0.0000646

Gnomad AMR exome AF: 0.0000581

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000393

Gnomad FIN exome AF: 0.000464

Gnomad NFE exome AF: 0.000901

Gnomad OTH exome AF: 0.000332

GnomAD4 exome AF: 0.000695 AC: 1015 AN: 1461096 Hom.: 1 Cov.: 31 AF XY: 0.000643 AC XY: 467 AN XY: 726834

African (AFR) AF: 0.000209 AC: 7 AN: 33448

American (AMR) AF: 0.0000448 AC: 2 AN: 44676

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26116

East Asian (EAS) AF: 0.000202 AC: 8 AN: 39566

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.000487 AC: 26 AN: 53390

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.000856 AC: 952 AN: 1111554

Other (OTH) AF: 0.000331 AC: 20 AN: 60344

GnomAD4 genome AF: 0.000394 AC: 60 AN: 152166 Hom.: 0 Cov.: 32 AF XY: 0.000242 AC XY: 18 AN XY: 74392

African (AFR) AF: 0.000120 AC: 5 AN: 41548

American (AMR) AF: 0.0000654 AC: 1 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3466

East Asian (EAS) AF: 0.000585 AC: 3 AN: 5128

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.000188 AC: 2 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.000706 AC: 48 AN: 67972

Other (OTH) AF: 0.000473 AC: 1 AN: 2114

Alfa AF: 0.000635 Hom.: 0

Bravo AF: 0.000397

TwinsUK AF: 0.000270 AC: 1

ALSPAC AF: 0.000778 AC: 3

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000603 AC: 5

ExAC AF: 0.000430 AC: 52

EpiCase AF: 0.000436

EpiControl AF: 0.000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:10 Benign:14

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:4 Benign:7

Aug 24, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The TTN c.57442A>G; p.Met19148Val variant (rs188185141; ClinVar Variation ID: 191935) is rare in the general population (<0.2% allele frequency in the Genome Aggregation Database) and has been reported in individuals with hypertrophic cardiomyopathy and arrhythmogenic cardiomyopathy (Lopes 2013, Mates 2018). The clinical relevance of rare missense variants in this gene, which are identified on average once per individual sequenced in affected populations (Herman 2012), is not well understood. Yet, evidence suggests that the vast majority of such missense variants do not contribute to the clinical outcome of DCM (Begay 2015). Thus, the clinical significance of the p.Met19148Val variant cannot be determined with certainty. References: Lopes LR et al. Genetic complexity in hypertrophic cardiomyopathy revealed by high-throughput sequencing. J Med Genet. 2013 Apr;50(4):228-39. PMID: 23396983. Mates J et al. Role of copy number variants in sudden cardiac death and related diseases: genetic analysis and translation into clinical practice. Eur J Hum Genet. 2018 Jul;26(7):1014-1025. PMID: 29511324. Begay RL et al. Role of Titin Missense Variants in Dilated Cardiomyopathy. J Am Heart Assoc. 2015 Nov 13;4(11). PMID: 26567375. Herman DS et al. Truncations of titin causing dilated cardiomyopathy. N Engl J Med. 2012 Feb 16;366(7):619-28. PMID: 22335739. Linke WA and Hamdani N. Gigantic business: titin properties and function through thick and thin. Circ Res 2014; 114(6): 1052-1068. PMID: 24625729.

Jun 24, 2013

Biesecker Lab/Clinical Genomics Section, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: research

Nov 30, 2016

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Apr 27, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Laboratory of Diagnostic Genome Analysis, Leiden University Medical Center (LUMC)

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Clinical Genetics, Academic Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

May 27, 2024

Revvity Omics, Revvity

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Genome Diagnostics Laboratory, University Medical Center Utrecht

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Sep 06, 2017

Eurofins Ntd Llc (ga)

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not specified Uncertain:1 Benign:3

Oct 10, 2017

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

proposed classification - variant undergoing re-assessment, contact laboratory

Mar 10, 2025

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: TTN c.49738A>G (p.Met16580Val) results in a conservative amino acid change located in the A-band region of the encoded protein sequence. Three of four in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.0005 in 248042 control chromosomes, predominantly at a frequency of 0.0009 within the Non-Finnish European subpopulation in the gnomAD database, including 1 homozygote. The observed variant frequency within Non-Finnish European control individuals in the gnomAD database is approximately 2-fold of the estimated maximal expected allele frequency for a pathogenic variant in TTN causing Dilated Cardiomyopathy phenotype (0.00039). c.49738A>G has been reported in the literature in at least one individual affected with Dilated Cardiomyopathy, witout strong evidence for causality (e.g. Martinez-Barrios_2022). This report does not provide unequivocal conclusions about association of the variant with Dilated Cardiomyopathy. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 35207729). ClinVar contains an entry for this variant (Variation ID: 191935). Based on the evidence outlined above, the variant was classified as likely benign.

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

Apr 09, 2025

Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Autosomal recessive limb-girdle muscular dystrophy type 2J Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1858763:Dilated cardiomyopathy 1G Uncertain:1

Dec 14, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Dilated cardiomyopathy 1G Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Early-onset myopathy with fatal cardiomyopathy Uncertain:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Autosomal recessive limb-girdle muscular dystrophy type 2J;C1838244:Tibial muscular dystrophy;C1858763:Dilated cardiomyopathy 1G;C1861065:Hypertrophic cardiomyopathy 9;C1863599:Myopathy, myofibrillar, 9, with early respiratory failure;C2673677:Early-onset myopathy with fatal cardiomyopathy Uncertain:1

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Cardiomyopathy Benign:1

Jan 03, 2020

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Myopathy, myofibrillar, 9, with early respiratory failure Benign:1

Jul 18, 2017

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign.

Tibial muscular dystrophy Benign:1

Jul 18, 2017

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign.

Cardiovascular phenotype Benign:1

May 06, 2020

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.38	T
BayesDel_noAF	Benign	-0.40
CADD	Benign	16
DANN	Benign	0.87
Eigen	Benign	-0.25
Eigen_PC	Benign	-0.032
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Uncertain	0.86	D
M_CAP	Benign	0.014	T
MetaRNN	Benign	0.029	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	-0.32	N
PhyloP100		1.9
PrimateAI	Benign	0.41	T
PROVEAN	Uncertain	-2.5	N
REVEL	Benign	0.14
Sift	Benign	0.098	T
Polyphen		0.065	B
Vest4		0.33
MVP		0.22
MPC		0.086
ClinPred		0.021	T
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		2.1
Mutation Taster		=99/1	polymorphism

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

Other links and lift over

dbSNP: rs188185141; hg19: chr2-179462367;